Exam II

Question 1

Briefly define metabolism

Answer 1

Metabolism is the sum of all chemical reactions within an organism.

Question 2

Briefly define metabolic pathway

Answer 2

A metabolic pathway is a sequence of enzymatically catalyzed chemical reactions that occur in a cell. The metabolism of a cell is composed of many metabolic pathways.

Question 3

What is the sum of all chemical reactions within an organism called?

Answer 3

Metabolism

Question 4

What is a sequence of enzymatically catalyzed chemical reactions that occur in a cell?

Answer 4

Metabolic pathways

Question 5

The metabolism of a cell is composed of many different what?

Answer 5

Metabolic pathways

Question 6

What are enzymatically catalyzed chemical reactions of a cell called?

Answer 6

Metabolic pathways

Question 7

What is anabolism?

Answer 7

Anabolism consists of enzyme-regulated chemical reactions that require the input of energy. Anabolism generally results in smaller of simpler organic molecules being built into larger or more complex molecules.

Question 8

What consists of enzyme-regulated chemical reactions that require the input of energy?

Answer 8

Anabolism

Question 9

What type of metabolism generally results in smaller of simpler organic molecules being built into larger or more complex molecules?

Answer 9

Anabolism

Question 10

Anabolism generally results in:

1) smaller or
2) larger organic molecules

being built into larger or more complex molecules?

Answer 10

Smaller

Question 11

Anabolism results in which one:

1) larger or more complex molecules or
2) smaller or simpler molecules

Answer 11

Larger

Question 12

Briefly define catabolism.

Answer 12

Catabolism consists of enzyme-regulated chemical reactions that release energy. Catabolism generally results in larger, more complex molecules being converted or broken down into smaller or simpler molecules.

Question 13

What type of metabolism consists of enzyme-regulated chemical reactions that release energy?

Answer 13

Catabolism

Question 14

What type of metabolism generally results in larger, more complex molecules being converted or broken down into smaller or simpler molecules?

Answer 14

Catabolism

Question 15

Does catabolism begin with larger or smaller molecules that are being converted as compared to anabolism?

Answer 15

Larger

Question 16

Catabolism results in the creation of smaller or larger molecules than anabolism?

Answer 16

Smaller

Question 17

Catabolism results in which one:

1) larger or more complex molecules or
2) smaller or simpler molecules

Answer 17

Smaller or simpler molecules

Question 18

What is an enzyme?

Answer 18

Enzymes are proteins that are capable of catalyzing chemical reactions.

Question 19

An enzyme has a specific pocket or surface that allows it to bind to a surface. What is this specific pocket called?

Answer 19

The active site

Question 20

What is the quality that allows an enzyme’s active site to specifically bind to specific substrate?

Answer 20

Same shape

Question 21

What is the name of the substance that binds to the active site on an enzyme?

Answer 21

Substrate

Question 22

What is a substrate?

Answer 22

The substance that is able to bind to an enzyme.

Question 23

What must bind to the enzyme to form a complex before the enzyme will be able to catalyze the reaction?

Answer 23

The substrate

Question 24

What does the binding of the enzyme and substrate called?

Answer 24

Enzyme-substrate complex

Question 25

What occurs first:

1) The enzyme catalyzes the reaction with the enzyme-substrate complex or
2) The substrate binds with the enzyme to form the enzyme-substrate complex?

Answer 25

2) The substrate binds with the enzyme to form the enzyme-substrate complex.

Question 26

What must happen before an enzyme will be able to catalyze the reaction that converts the substrate into the product?

Answer 26

The substrate must bind to the enzyme

Question 27

What is the result called when an enzyme-substrate complex is catalyzed?

Answer 27

The product

Question 28

What is the name of the end result of an enzyme-substrate complex that has been catalyzed?

Answer 28

The product

Question 29

Enzyme + substrate + reaction = what

Answer 29

The product

Question 30

Define the product of an enzymatic reaction?

Answer 30

The result of the substrate binding to the enzyme to form the enzyme-substrate complex that is than catalyzed.

Question 31

Conversion of the substrate into the product in an enzymatic process requires which of the following:

1) an enzyme
2) binding of the substrate to the enzyme
3) a substrate

Answer 31

All three:

1) an enzyme
2) binding of the substrate to the enzyme
3) a substrate

Question 32

What is the binding of an enzyme to the active site sometimes called?

Answer 32

Lock and key fit

Question 33

What does “lock and key” refer to in the topic of enzymes?

Answer 33

It refers to the fit between the substrate and the active site on an enzyme.

Question 34

Each substrate will fit into different shaped active sites on enzymes or specifically-shaped active sites?

Answer 34

Specifically shaped

Question 35

True/False

Each substrate will fit a specific enzyme in a way like each key fits a specific lock.

Answer 35

True

Question 36

True/False

Some substrates cause parts of the active site of the enzyme to move.

Answer 36

True, it’s called the “induced fit model.”

Question 37

Why do some substrates, like in the induced fit model, cause parts of the active site of an enzyme to move?

Answer 37

To allow a tighter fit between the enzyme and substrate.

Question 38

What do some substrates do to allow a tighter fit with an enzyme?

Answer 38

They cause parts of the active site on an enzyme to move (called the induced fit model).

Question 39

Describe the steps in an enzymatic reaction.

Answer 39

1. Substrate enters active site; enzyme changes shape such that its active site enfolds the substrate (induced fit).
2. Substrates held in active site by weak interactions such as hydrogen bonds and ionic bonds.
3. Active site can lower E_A and speed up a reaction.
4. Substrates are converted to products.
5. Products are released.
6. Active site is available for two new substrate molecules.
   7.

Question 40

What does E_A mean in an qnzymatic reaction?

Answer 40

Activation energy

Question 41

What does ∆G mean?

Answer 41

Gibbs free energy, which is the amount of energy required for or released by a reaction, which is the difference in the chemical energy of the starting molecule (the substrate) from the product.

Question 42

How do enzymes affect ∆G?

Answer 42

Enzymes do not affect ∆G.

Question 43

How do enzymes affect the activation energy of a chemical reaction?

Answer 43

Enzymes and other catalysts allow chemical reactions to occur more quickly or more often by lowering the activation energy required for the chemical reaction.

Question 44

What catalyst lowers the activation energy required for a chemical reaction?

Answer 44

An enzyme

Question 45

What is the substance called that lowers activation energy?

Answer 45

A catalyst. Enzymes are catalysts.

Question 46

Can a chemical reaction occur without an enzyme and why?

Answer 46

Yes, a chemical reaction could occur without an enzyme but enzymes lower the activation energy of the reaction.

Question 47

How do competitive and non-competitive inhibitors inhibit the action of enzymes?

Question 48

What is an inhibitor?

Answer 48

Small molecules that prevent enzymes from catalyzing chemical reactions.

Question 49

Why do cells use inhibitors?

Answer 49

Inhibitors control chemical reactions, making specific inhibitors to turn off specific chemical reactions.

Question 50

What do cells use to control chemical reactions or to turn off specific reactions?

Answer 50

Inhibitors

Question 51

What are competitive inhibitors?

Answer 51

Inhibitors that bind to the active site of a specific enzyme and prevent the substrate from binding.

Question 52

What binds to the active site of a specific enzyme and prevents the substrate from binding?

Answer 52

Competitive inhibitors

Question 53

What binds directly to the active site on an enzyme and directly competes for binding with the substrate?

Answer 53

A competitive inhibitor

Question 54

What is a non-competitive inhibitor?

Answer 54

A non-competitive inhibitor binds to a part of the enzyme other than the active site, referred to as an allosteric site. By binding to the allosteric site, the non-competitive inhibitor causes a change in the shape of the enzyme, most importantly in the active site, which prevents the substrate from binding to the distorted active site.

Question 55

What binds to the active site of a specific enzyme and prevents the substrate from binding?

Answer 55

A competitive inhibitor

Question 56

A non-competitive inhibitor binds to a part of the enzyme other than the active site, referred to as what?

Answer 56

The allosteric site

Question 57

What part of the enzyme does a non-compeitive inhibitor bind to?

Answer 57

The allosteric site.

Question 58

What is an allosteric site?

Answer 58

The site on an enzyme that a non-compeitive inhibitor binds to.

Question 59

What do a competitive inhibitor and a non-competitive inhibitor have in common?

Answer 59

They both prevent a substrate from binding to the active site, therefore preventing the enzyme-substrate complex from forming and will not be able to catalize the reaction and form products.

Question 60

What two substrances prevent an enzyme-substrate complex from forming?

Answer 60

A competive inhibitor and a non-competitive inhibitor.

Question 61

What happens when a non-competitive inhibitor binds with the allosteric site on an enzyme?

Answer 61

The non-competitive inhibitor causes a change in the shape of the enzyme, most importantly the active site, which prevents the substrate from binding to the distorted active site.

Question 62

What can bind to the allosteric site on an enzyme and cause the enzyme to distort?

Answer 62

A non-competitive inhibitor

Question 63

What is ATP short for?

Answer 63

Adenosine triphosphate

Question 64

What type of molecule is adenosine triphosphate?

Answer 64

One of the nucleotides used to make RNA.

Question 65

What is ATP used for?

Answer 65

Used by cells to store chemical energy in a readily-accessible format.

Question 66

What is adenosine triphosphate used for?

Answer 66

Used by cells to store chemical energy in a readily-accessible format (stores energy, acts like a rechargable battery).

Question 67

Where is energy stored in an ATP molecule?

Answer 67

ATP has three phosphate groups joined in a chain and the covalent bonds that join these phosphate groups contain a relatively large amount of chemical energy.

Question 68

How is energy stored in ATP?

Answer 68

ATP has three phosphate groups joined in a chain and the covalent bonds that join these phosphate groups contain a relatively large amount of chemical energy.

Question 69

Give three examples of enzymes.

Answer 69

• ATP synthase
• Catalase
• DNA polymerase

Question 70

What are

• ATP synthase
• Catalase
• DNA polymerase

Answer 70

Enzymes

Question 71

What is ATP synthase?

Answer 71

An enzyme

Question 72

What is catalase?

Answer 72

An enzyme

Question 73

What is DNA polymerase?

Answer 73

An enzyme

Question 74

What is the structure of ATP?

Answer 74

Adenine, ribose sugar and three phosphate groups joined in a chain.

Question 75

What are the bonds in which ATP stores energy?

Answer 75

The covalent bonds that join the three phosphate groups in a chain contain a relatively large amount of chemical energy.

Question 76

What is the type of energy stored in the covalent bonds of ATP?

Answer 76

Chemical energy

Question 77

How is ATP converted to ADP?

Answer 77

Breaking one of the bonds converts ATP (adenosine triphosphate) to ADP (adenosine diphosphate) and Pi (an inorganic phosphate) and releases chemical energy.

Question 78

Breaking one of the bonds leads to a release of chemical energy in cellular metabolism and the conversion of what to what?

Answer 78

Converting ATP to ADP

Question 79

What is the formula for the hydrolysis of ATP?

Answer 79

ATP + H₂O = ADP + Pi (inorganic phosphate) + energy

Question 80

Cells can capture chemical energy by using it to convert ADP and Pi to what?

Answer 80

ATP

Question 81

What happens to the cell when ADP + Pi is converted to ATP?

Answer 81

Energy is captured

Question 82

What happens in catabolic pathways to energy and ATP?

Answer 82

• Energy is used to make ATP
• Will have a gain of ATP

Question 83

Energy is used to make ATP and the cell will have a gain of ATP in what pathway?

Answer 83

Catabolic pathways

Question 85

What happens in anabolic pathways to energy and ATP?

Answer 85

• Energy is supplied as ATP
• Will have a loss of ATP (Anabolic pathways require energy)

Question 86

True/False

Catabolic reactions transfer energy from complex molecules to ATP?

Answer 86

True. Catabolic reactions break down larger molecules, such as carbohydrates, lipids, and proteins from ingested food, into smaller molecules.

Catabolic reactions also breakdown complex molecules to ATP.

Question 87

True/False

Anabolic reactions transfer energy from ATP to complex molecules.

Answer 87

True. Anabolic reactions synthesize larger molecules from smaller ones, using ATP as the energy source for these reactions.

Question 88

Are electrons lost or gained in oxidation reactions?

Answer 88

Electrons are lost

Question 89

When electrons are lost in a reaction, what type is this?

Answer 89

Oxidation

Question 90

Oxidation reactions involve the loss/gain of electrons?

Answer 90

Loss of electrons

Question 91

What’s it called when electrons are gained in a chemical reaction?

Answer 91

Reduction reaction

Question 92

What is a reduction reaction?

Answer 92

A chemical reaction whereby electrons are gained

Question 93

In a reduction reactions, what happens to electrons?

Answer 93

Electrons are gained

Question 94

What’s the difference between a reduction and an oxidation reaction?

Answer 94

In a reduction reaction, electrons are gained.

In an oxidation reactions, electrons are lost.

Question 95

In a(n) ________ reactions, electrons are lost.

In a(n) _________ reaction, electrons are gained.

Answer 95

In a(n) oxidation reactions, electrons are lost.

In a(n) reduction reaction, electrons are gained.

Question 96

Since electrons cannot be created or destroyed, what will always be linked to an oxidation reaction?

Answer 96

A reduction reaction

Question 97

An oxidation reaction will always be linked to what other type of reaction?

Answer 97

A reduction reaction

Question 98

Why are reduction and oxidation reactions always linked?

Answer 98

Because you can neither create nor destroy electrons.

Question 99

Generally, with organic molecules, this type of reaction will lead to a gain of oxygen atoms and a loss of hydrogen atoms.

Answer 99

Oxidation

Question 100

Oxidation reactions lead to a loss or gain of oxygen atoms and a loss or gain of hydrogen atoms.

Answer 100

Oxidation reactions lead to a gain of oxygen atoms and a loss of hydrogen atoms.

Question 101

A molecule that is oxidized, could end up with more _____ atoms and fewer _____ atoms than when it started.

Answer 101

Oxygen, hydrogen

Question 102

A molecule that is reduced, could end up with loss of _____ atoms and a gain of _____ atoms than when it started.

Answer 102

Oxygen, hydrogen

Question 103

Oxygen and hydrogen atoms are lost or gained in a reduction reaction?

Answer 103

Hydrogen gained, oxygen lost

Question 104

Describe the role of electron carriers in the cell.

Answer 104

Electron carriers are molecules that are used to transfer (relatively high energy) electrons between metabolic pathways.

Reactions involving electron carriers will always be oxidation-reduction reactions.

Question 105

Electron carriers are molecules that will always transfer electrons by what type of reactions?

Answer 105

Oxidation-reduction reactions

Question 106

Oxidation-reduction reactions are indicative of what type of carriers that transfer electrons in metabolism?

Answer 106

Electron carriers

Question 107

What is transferred using NAD⁺, FAD and NADP⁺ in metabolism?

Answer 107

Electrons

Question 108

If the electron carrier is oxidized over the course of a reaction, another molecule in the reaction will be ____________.

Answer 108

Reduced

Question 109

If the electron carrier is reduced over the course of a reaction, another molecule in the reaction will be ____________.

Answer 109

Oxidized

Question 110

What type of reactions do electron carriers use to transfer electrons?

Answer 110

Oxidation-reduction reactions

Question 111

Name the oxidized forms of three electron carriers involved in metabolism.

Answer 111

NAD⁺ (reduced to NADH)

FAD (reduced to FADH₂)

NADP⁺ (reduced to NADPH)

(Note: Each electron carrier will pick up or donate 2 electrons)

Question 112

Name the reduced forms of the three electron carriers involved in metabolism.

Answer 112

NADH (oxidized to NAD⁺ + H⁺)

FADH₂ (oxidized to FAD + 2H⁺)

NADPH (oxidized to NADP⁺ + H⁺)

(Note: Each electron carrier will pick up or donate 2 electrons)

Question 113

NADH is the oxidized or reduced form of NAD⁺ + H⁺?

Answer 113

Reduced

Question 114

FAD + 2H⁺ is the oxidized or reduced form of FADH₂?

Answer 114

Oxidized

Question 115

NADPH is the oxidized or reduced form of NADP⁺ + H⁺?

Answer 115

Reduced

Question 116

NAD⁺ + H⁺ is the oxidized or reduced form of NADH?

Answer 116

Oxidized

Question 117

FAD + 2H⁺ is the oxidized or reduced form of FADH²?

Answer 117

Oxidized

Question 118

NADP⁺ + H⁺ is the oxidized or reduced form of NADPH?

Answer 118

Oxidized

Question 119

In oxidation-reduction reactions with electron carriers, how many electrons are picked up or donated?

Answer 119

2 electrons:

NAD⁺ + H⁺ = NADH

FAD + 2H⁺ = FADH₂

NADP⁺ + H⁺ = NADPH

Question 120

In oxidation reactions involving electron carriers, are two electrons picked up or donated?

Answer 120

Donated

Question 121

In reduction reactions involving electron carriers, are two electrons picked up or donated?

Answer 121

Picked up

Question 123

True/False

NADH is oxidized to NAD⁺ + H⁺

FADH₂ is reduced to FAD + 2H⁺

NADPH is oxidized to NADP⁺ + H⁺

Answer 123

True

False

True

Question 124

True/False

NAD⁺ + H⁺ is reduced to NADH

FADH₂ is oxidized to FAD + 2H⁺

NADP⁺ + H⁺ is reduced to NADPH

Answer 124

True

True

True

Question 125

Describe the energy requirements and carbon requirements of chemoheterotrophs.

Answer 125

Chemoheterotrophs.

Prefixes that describe chemical requirements:

• Chemo - must use oxidation-reduction reactions to obtain chemical energy
• Photo - can use light to obtain chemical energy (may also be able to use oxidation-reduction reactions)

Prefixes that describe carbon requirements:

• Hetero - must use larger organic molecules as the starting point for anabolism
• Auto - can use CO2 as the starting point for anabolism (may also be able to use larger organic molecules)

Question 126

Describe the energy requirements and carbon requirements of chemoautotrophs.

Answer 126

Chemoautotrophs.

Prefixes that describe chemical requirements:

• Chemo - must use oxidation-reduction reactions to obtain chemical energy
• Photo - can use light to obtain chemical energy (may also be able to use oxidation-reduction reactions)

Prefixes that describe carbon requirements:

• Hetero - must use larger organic molecules as the starting point for anabolism
• Auto - can use CO2 as the starting point for anabolism (may also be able to use larger organic molecules)

Question 127

Describe the energy requirements and carbon requirements of photoheterotrophs.

Answer 127

Photoheterotrophs.

Prefixes that describe chemical requirements:

• Chemo - must use oxidation-reduction reactions to obtain chemical energy
• Photo - can use light to obtain chemical energy (may also be able to use oxidation-reduction reactions)

Prefixes that describe carbon requirements:

• Hetero - must use larger organic molecules as the starting point for anabolism
• Auto - can use CO2 as the starting point for anabolism (may also be able to use larger organic molecules)

Question 128

Describe the energy requirements and carbon requirements of photoautotrophs.

Answer 128

Photoautotrophs.

Prefixes that describe chemical requirements:

• Chemo - must use oxidation-reduction reactions to obtain chemical energy
• Photo - can use light to obtain chemical energy (may also be able to use oxidation-reduction reactions)

Prefixes that describe carbon requirements:

• Hetero - must use larger organic molecules as the starting point for anabolism
• Auto - can use CO2 as the starting point for anabolism (may also be able to use larger organic molecules)

Question 129

What are the prefixes that describe energy requirements?

Answer 129

Prefixes that describe chemical requirements:

• Chemo - must use oxidation-reduction reactions to obtain chemical energy
• Photo - can use light to obtain chemical energy (may also be able to use oxidation-reduction reactions)

Question 130

What are the prefixes that describe carbon requirements?

Answer 130

Prefixes that describe carbon requirements:

• Hetero - must use larger organic molecules as the starting point for anabolism
• Auto - can use CO2 as the starting point for anabolism (may also be able to use larger organic molecules)

Question 131

What are the four different combinations of energy and carbon requirements involved in trophism?

Answer 131

Question 132

What does this chart represent?

Answer 132

The energy and carbon requirements involved in trophism

Question 133

All organisms need what two things?

• Hint:
  
  • Powers anabolic reactions (and other things)
• Hint:
  
  • Starting point for anabolic reactions

Answer 133

Source of energy, source of carbon

Question 134

Why do all organisms use a source of energy and a source of carbon for?

Answer 134

A source of energy powers anabolic reactions (and other things).

A source of carbon is the starting point for anabolic reactions.

The point is all living organisms need to reproduce (make more cells) and other things.

Question 135

List the three metabolic pathways involved in cellular respiration.

Answer 135

• Glycolysis
  
  • Preparatory stage
  • Energy-conserving stage
• The Krebs cycle aka tricarboxylic acid cycle or TCA cycle
  
  • Decarboxylation
  • Citric acid cycle
• Oxidative phosphorylation
  
  • Eectron transport
  • Chemiosmosis

Question 136

What is the tricarboxylic acid cycle or TCA cycle?

Answer 136

The TCA is another name for the Krebs Cycle or the Citric Acid Cycle.

Question 137

Enzymes bind through 2 models. Name them.

Answer 137

• Specificity
  
  • Lock and key model
  • The active site of an enzyme is specific to its substrate
• Induced fit model
  
  • Binding to the substrate causes the enzyme to bind it more tightly

Question 138

What does the lock and key model of enzyme binding mean?

Answer 138

It means that the active site of an enzyme is specific to its substrate, like a lock and key.

Question 139

True/False

Specificity is important in regard to how enzymes work.

Answer 139

True

Question 140

The induced fit model refers to what microbiological molecule?

Answer 140

Enzymes

Question 141

Binding to a substrate causes the enzyme to bind it more tightly is what model?

Answer 141

Induced fit model

Question 142

What are the two metabolic pathways involved in fermentation?

Answer 142

1. Glycolysis
2. Secondary fermentation reactions

Question 143

Glycolysis and a secondary fermentation reaction are pathways involved in what type of metabolic process?

Answer 143

Fermentation

Question 144

Fermentation is dependent on what two pathways?

Answer 144

1. Glycolysis
2. Secondary fermentation process

Question 145

What molecules are the initial electron donors and final electron acceptors in aerobic cellular respiration?

Answer 145

Initial: glucose

Final: H₂O

Question 146

O₂ is reduced to what as the final electron acceptor in aerobic cellular respiration?

Answer 146

H₂O

Question 147

H₂O is what the final electron acceptor in aerobic cellular respiration is reduced to. What is the final electron acceptor?

Answer 147

O₂

Question 148

What is the initial electron donor in aerobic cellular respiration?

Answer 148

O₂

Question 149

What molecules are the initial electron donors and final electron acceptors in fermentation?

Answer 149

1. Glucose
2. Organic molecule derived from glucose (is reduced to the fermentaion end produce, e.g. lactic acid or ethanol)

Question 150

What do aerobic cellular respiration and fermentation have in common?

Answer 150

The initial electron donor is glucose.

Question 151

Glucose and an organic molecule derived from glucose play what roles in fermentation?

Answer 151

Glucose is the initial electron donor.

An organic molecule derived from glucose is the final electron acceptor.

Question 152

Breaking down carbohydrates (glucose) to produce energy (turn ADP into ATP) involves what two main processes?

Answer 152

• Cellular respiration
  
  • Aerobic
  • Anaerobic
• Fermentation

Question 153

These two main processes do what in a metabolic pathway: Cellular respiration (aerobic and anerobic) and fermentation?

Answer 153

Carbohydrate catabolism (breaking down carbohydrates to produce energy).

Question 154

What is the process by which carbohydrates are broken down to produce energy?

Answer 154

Carbohydrate catabolism

Question 155

What molecule is broken down to produce energy and what molecules represent that energy?

Answer 155

Glucose is broken down to turn ADP into ATP.

Question 156

What is the energy that is produced in carbohydrate catabolism?

Answer 156

ATP (ADP is turned into ATP)

Question 157

Glucose is what type of macromolecule?

Answer 157

Carbohydrate

Question 158

How much ATP is produced in aerobic cellular respiration?

Answer 158

Produces a large amount of ATP (up to 38 ATP per glucose)

Question 159

A large amount of ATP (38) is produced through what metabolic pathway?

Answer 159

Aerobic cellular respiration

Question 160

What molecule is catabolized in fermentation to produce 2 ATP?

Answer 160

Glucose

Question 161

How much ATP is produced in fermentation?

Answer 161

A small amount (2 ATP per glucose molecule)

Question 162

2 ATP per glucose are produced by what metabolic pathway?

Answer 162

Fermentation

Question 163

What metabolic pathways produce 2 ATP and 38 ATP respectively?

Answer 163

Fermentation, aerobic cellular respiration

Question 164

Aerobic cellular respiration and fermentation produce ATP from what molecule?

Answer 164

Glucose

Question 165

What molecule is catabolized in aerobic cellular respiration to produce 38 ATP?

Answer 165

Glucose

Question 166

Do aerobic cellular respiration and fermentation both use carbohydrate catabolism?

Answer 166

Yes

Question 167

What is the generic reaction for aerobic cellular respiration?

Answer 167

C₆H₁₂O₆ + 6 O₂ —–> 6 CO₂ + 6 H₂O

Question 168

In this reaction, what molecule is the carbohydrate?

C₆H₁₂O₆ + 6 O₂ —–> 6 CO₂ + 6 H₂O

Answer 168

C₆H₁₂O₆

Question 169

In this reaction, what molecule is the initial electron donor?

C₆H₁₂O₆ + 6 O₂ —–> 6 CO₂ + 6 H₂O

Answer 169

C₆H₁₂O₆

Question 170

In this reaction, what molecule is the final electron acceptor?

C₆H₁₂O₆ + 6 O₂ —–> 6 CO₂ + 6 H₂O

Answer 170

O₂

Question 171

In this reaction, what molecule is the final electron acceptor reduced to?

C₆H₁₂O₆ + 6 O₂ —–> 6 CO₂ + 6 H₂O

Answer 171

H₂O

Question 172

In this reaction, what are the ADP, inorganic phosphate and ATP used/produced on each side of the equation?

C₆H₁₂O₆ + 6 O₂ —–> 6 CO₂ + 6 H₂O

Answer 172

C₆H₁₂O₆ + 6 O₂ —–> 6 CO₂ + 6 H₂O

38 ADP + Pi —-> 38 ATP

Question 173

True/False

Since molecules can enter aerobic cellular respiration at various points in the cyle, the amount of energy gained from various molecules (protein, carbohydrate and lipids) is based on where they enter cycle.

Answer 173

True

Question 174

Proteins can enter aerobic cellular respiration at which metabolic pathways?

Answer 174

Glycolysis, decarboxylation and the Krebs Cycle

Question 175

Carbohydrates can enter aerobic cellular respiration at which metabolic pathways?

Answer 175

Glycolysis

Question 176

Lipids can enter aerobic cellular respiration at which metabolic pathways?

Answer 176

Glycolycis and decarboxylation

Question 177

Do all enzymes have an allosteric site?

Answer 177

No.

Question 178

Label each reaction as reduced or oxidized:

• NAD⁺ + H⁺ to NADH
• FADH₂ to FAD + 2H⁺
• NADP⁺ + H⁺ to NADPH

Answer 178

• NAD⁺ + H⁺ is reduced to NADH
• FADH₂ is oxidized to FAD + 2H⁺
• NADP⁺ + H⁺ is reduced to NADPH

Question 179

Is the tricarboxylic acid cycle another name for the Krebs Cycle and the Citric Acid Cycle?

Answer 179

Yes.

Question 180

What’s another name for the tricarboxylic acid cycle?

Answer 180

The Krebs Cycle or the Citric Acid Cycle.

Question 181

What’s another name for the Krebs Cycle?

Answer 181

The Citric Acid cycle or the tricarboxylic acid cycle.

Question 182

Are the following true about this reaction? C6H12O6 + 6 O2 —–> 6 CO2 + 6 H2O

• The initial electron donor is C6H12O6 (the glucose molecule)
• The final electron acceptor is O2
• The final electron acceptor is reduced to H2O
• CO2 is an ending organic molecule

Answer 182

All true.

Question 183

In what metabolic process do the following occur?

• The initial electron donor is C6H12O6 (the glucose molecule)
• The final electron acceptor is O2
• The final electron acceptor is reduced to H2O
• CO2 is an ending organic molecule

Answer 183

Aerobic cellular respiration

Question 184

What is the general chemical formula for the metabolic process that results in the following and what is the name of that metabolic process?

• The initial electron donor is C₆H₁₂O₆ (the glucose molecule)
• The final electron acceptor is O₂
• The final electron acceptor is reduced to H₂O
• CO₂ is an ending organic molecule

Answer 184

Aerobic cellular respiration

C₆H₁₂O₆ + 6 O₂ —–> 6 CO₂ + 6 H₂O

Question 185

Does the statement: “The amount of energy gained from various molecules is based on where they enter cycle” pertain only to aerobic cellular respiration?

Answer 185

No, it also refers to fermentation.

Question 186

At what stages of aerobic cellular respiration can protein enter?

Answer 186

Glycolysis, decarboxylation and the Krebs Cycle.

Question 187

What macromolecule can enter aerobic cellular respiration at these stages: Glycolysis, decarboxylation and the Krebs Cycle.

Answer 187

Proteins

Question 188

At what stage in aerobic cellular respiration can carbohydrates enter?

Answer 188

Glycolysis

Question 189

What macromolecule can enter aerobic cellular respiration only at glycolysis?

Answer 189

Carbohydrates

Question 190

Lipids can enter aerobic cellular respiration at which stages?

Answer 190

Glycolysis and decarboxylation.

Question 191

Which macromolecule can enter aerobic cellular respiration at both glycolysis and decarboxylation but not the Krebs Cycle?

Answer 191

Lipids

Question 192

What are the three stages of aerobic cellular respiration?

Answer 192

Glycolysis, the Krebs Cycle and oxidative phosphorylation

Question 193

Glycolysis, the Krebs Cycle and oxidative phosphorylation are three stages of what?

Answer 193

Aerobic cellular respiration

Question 194

What is this reaction: C6H12O6 + 6 O2 (+38 ADP + 38Pi) —-> 6CO2 + 6H2O (+38 ATP)

Answer 194

Aerobic cellular respiration.

Question 195

What is the chemical formula for aerobic cellular respiration?

Answer 195

C6H12O6 + 6O2 (+38 ADP + Pi) —-> 6CO2 + 6H2O (+38 ATP)

Question 196

How many carbon dioxide and water molecules are produced in aerobic cellular respiration?

Answer 196

Six

C6H12O6 + 6O2 (+38 ADP + 38Pi) —-> 6CO2 + 6H20 (+38 ATP)

Question 197

How many glucose molecules does it take to produce 12 CO2 molecules in aerobic cellular respiration?

Answer 197

Two glucose molecules

C6H12O6 + 6O2 (+38 ADP + 38Pi) —-> 6CO2 + 6 H20 (+38 ATP)

Question 198

Where do ADP + Pi and ATP belong in this chemical equation, how many and what is the reaction?

C6H12O6 + 6O2 —-> 6CO2 + 6 H20

Answer 198

C6H12O6 + 6O2 (+38 ADP + 38Pi) —-> 6CO2 + 5 H20 (+38 ATP)

Aerobic cellular respiration

Question 199

What is similar between aerobic and anerobic cellular respiration?

Answer 199

Both aerobic and anaerobic cellular fermentation are the same in that they use the same three processes:

glycolysis, Krebs Cycle and oxidative phosphorylation (or equivalent) reactions.

Question 200

Which two metabolic pathways use the same three processes: glycolysis, Krebs Cycle and oxidative phosphorylation (or equivalent (reactions).

Answer 200

Aerobic and anaerobic cellular respiration use the same three pathways.

Question 201

Using the processes of glycolysis, the Krebs Cycle and oxidative phosphorylation (or equivalent) are characteristics of what two metabolic pathways?

Answer 201

Aerobic and anaerobic cellular respiration

Question 202

What is the difference between the aerobic and anaerobic cellular respiration pathways?

Answer 202

The two main differences are the final electron acceptor and the amount of ATP produced.

Aerobic: final electron acceptor is O2, ATP = 38

Anaerobic: final electron acceptor is an inorganic molecule other than O2, ATP = 2

Question 203

What two metabolic pathways are being referred to with this statement: “The two main differences are the final electron acceptor and the amount of ATP produced.”

Answer 203

Aerobic and anaerobic cellular respiration.

Question 204

What is the final electron acceptor in aerobic cellular respiration?

Answer 204

O₂

Question 205

T/F

Aerobic cellular respiration does not use O₂ as the final electron acceptor.

Answer 205

False.

Aerobic cellular respiration uses O2 as the final electron acceptor while anaerobic cellular respiration uses a different molecule (usually inorganic).

Question 206

What is the final electron acceptor in anaerobic cellular respiration?

Answer 206

A different (usually inorganic) molecule than O₂.

Question 207

What are final electron acceptors in aerobic and anaerobic cellular respiration?

Answer 207

Aerobic = O2

Anaerobic = a different (usually inorganic) molecule

Question 208

T/F

Anaerobic celllular respiration will always produce more energy than aerobic.

Answer 208

False.

Aerobic respiration, because the final electron acceptor, O2, is able to accept lower energy elecrons than the final electron acceptors used by anaerobic cellular respiration, will always produce more energy than anaerobic.

Question 209

Which version of cellular respiration (aerobic or anaerobic) produces more energy and why?

Answer 209

Aerobic cellular respiration produces more energy (ATP) because O2 is able to accept lower energy electrons than the final electron acceptors in anaerobic cellular respiration.

Question 210

What molecule represents the energy produced by aerobic and anaerobic cellular respiration?

Answer 210

ATP (Adenosine triphosphate)

Question 211

The amount of ATP produced in anaerobic cellular respiration varies based on what two factors?

Answer 211

Type of organism and the pathway used.

Question 212

Fill-in-the-blank

Because glycolysis and the Krebs cycle are involved, anerobic cellular respiration will always produce more _____ than fermentation?

Answer 212

ATP

Question 213

Why will anaerobic cellular respiration always produce more ATP than fermentation?

Answer 213

Because anaerobic cellular respiration uses glycolysis and the Krebs Cycle while fermentation only uses glycolysis and a secondary fermentation reaction.

Question 214

Explain why cellular respiration produces more ATP than fermentation.

Answer 214

Fermentation produces only small amounts of ATP (only two molecules for each molecule of starting material) because so much of the original energy in glucose remains in the chemical bonds of the organic end-products, such as lactic acid or ethanol. Respiration is able to fully use this energy by converting the reactants to CO₂ and using the resulting electrons to power the electron transport chain to make ATP.

Question 215

Fermentation produces how many molecules of ATP for each molecule of starting material?

Answer 215

2 ATP

Question 216

Why does fermentation produce only small amounts of ATP?

Answer 216

Because so much of the original energy in glucose remains in the chemical bonds of the organic end-products, such as lactic acid or ethanol. Respiration is able to fully use this energy by converting the reactants to CO₂ and using the resulting electrons to power the electron transport chain to make ATP.

Question 217

Where does much of the original energy in glucose remain in fermentation?

Answer 217

In the chemical bonds of the organic end products, such as lactic acid or ethanol.

Question 218

From the original energy in glucose, what remains in the chemical bonds of the organic end-products, such as lactic acid or ethanol in fermentation?

Answer 218

Energy

Question 219

What is cellular respiration able to fully use by converting the reactants to CO₂ and using the resulting electrons to power the electron transport chain (fermentation cannot do this)?

Answer 219

Energy

Question 220

Cellular respiration is able to fully use energy by converting the reactants to ______ and using the resulting electrons to power the electron transport chain.

Answer 220

CO₂

Question 221

In respiration, the original energy in glucose is fully used by converting ______ to CO₂ and using the resulting electrons to power the electron transport chain to make ATP.

Answer 221

… the reactants…

Question 222

In respiration, the original energy in glucose is fully used by converting the reactants to CO2 and using the resulting electrons to power ____________ to make ATP.

Answer 222

… the electron transport chain…

Question 223

In what type of metabolic pathway is the original energy in glucose fully used by converting the reactants to CO₂ and using the resulting electrons to power the electron transport chain to make ATP.

Answer 223

Cellular respiration

Question 224

Since O₂ is able to accept very low energy electrons, what does that mean for aerobic cellular respiration vs. anaerobic?

Answer 224

Make more ATP (38) vs. anaerobic (2)

Question 225

What is the main reason why cellular respiration produces more ATP than fermentation?

Answer 225

It uses O₂ as the final electron acceptor.

Question 226

Why does using O₂ as the final electron acceptor help aerobic cellular respiration produce more ATP?

Answer 226

Because O₂ can accept very low energy electrons, which means that more energy can be used to make ATP.

Question 227

What does fermentation use as the final electron acceptor?

Answer 227

An organic molecule derived from glucose.

Question 228

Why does fermentation use an organic molecule derived from glucose as the final electron acceptor?

Answer 228

Because these molecules will only accept higher energy eleectrons, which means that there is less energy available to make ATP.

Question 229

T/F

Fermentation uses a final electron acceptor derived from glucose (not O₂) that will only accept higher energy electrons.

Answer 229

True

Question 230

Why does fermentation yield less energy than cellular respiration?

Answer 230

Because fermentation uses an organic molecule derived from glucose as the final electron acceptor. These molecules will only accept higher energy electrons which means that there is less energy available to make ATP.

Question 231

When the final electron acceptor in a metabolic pathway will only accept higher energy electrons, how does that affect energy production?

Answer 231

There will be less energy available to make ATP.

Question 232

List types of foods or beverages produced by bacterial fermentation.

Answer 232

1. Microorganisms that produce lactic acid as a fermentation end product are used to make fermented milk products (yogurts and cheeses), sauerkraut and kimchi.
2. Yeasts produce ethanol and CO2 through fermentation. The ethanol is used to make alcoholic beverages, while the CO₂ is used to make leavened baked goods.
3. Some microorganisms produce acetic acid through fermentation which is used to make vinegars.

Question 233

Fermented milk products (yogurts and cheeses), sauerkraut and kimchi and made by microorganisms that produce what?

Answer 233

Lactic acid

Question 234

What is the fermentation end product of the organisms used to make fermented milk products (yogurts and cheeses), sauerkraut and kimchi?

Answer 234

Lactic acid

Question 235

Lactic acid is the fermentation end product of the organisms used to make what foods?

Answer 235

Fermented milk products (yogurts and cheeses), sauerkraut and kimchi

Question 237

Yogurt, cheese, sauerkraut, kimchi, leavened baked goods and vinegars are produced using what type of metabolic pathway?

Answer 237

Fermentation

Question 238

What do yeasts produce through fermentation and what are these products used for?

Answer 238

Ethanol and CO2; used to make alcoholic beverages and leavened baked goods

Question 239

Alcohol and leavened baked goods are produced by microorganisms that produce what?

Answer 239

Ethanol and CO₂

Question 240

What are the microorganisms that are used to produce alcohol and leavened baked goods?

Answer 240

Yeasts

Question 241

Some microorganisms produce _______ through fermentation that are used to make vinegars?

Answer 241

Acetic acid

Question 242

Acetic acid through fermentation is used to make what product?

Answer 242

Vinegar

Question 243

Test results for review:

• Carbohydrate fermentation assays
  
  • pH indicator: phenol red - red at neutral, yellow at acidic
  • Gas indicator: inverted Durham tube

Answer 243

What two indicators are tested by carbohydrate fermentation assays?

Question 244

Test results for review:

• MRVP test (methyl red and Voges-Proskauer) differentiate between Escherichia coli and Enterobacter cloacae
  
  • pH indicator: methyl red - red at acidic (E. coli at 4.5 pH)
  • Acetoin presence - Enterobacter produces acetoin, red/pink with ring around surface of culture

Answer 244

Name the two indicators tested for in the MRVP test?

Question 245

What is the name of the MRVP test and for what is it an indicator?

Answer 245

Methyl red and Voges-Proskauer

Differentiate between Escherichia coli and Enterobacter cloacae.

Question 246

How do carbohydrate fermentation assays detect production of acid and/or gas as a result of fermentation?

Answer 246

Carbohydrate fermentation assays use a pH indicator and an overturned Durham tube to detect production of acid and gas as a result of fermentation. The pH indicator (phenol red) is red at neutral pH and yellow in acidic pH. The overturned Durhan tube is initally filled with media, but will collect any produced gas, which will form a bubble in the tube.

Question 247

What is it that uses a pH indicator and an overturned Durham tube to detect production of acid and gas as a result of fermentation?

Answer 247

Carbohydrate fermentation assays

Question 248

What is the carbohydrate fermentation assay that is used as a pH indicator?

Answer 248

Phenol red

Question 249

What color is the carbohydrate fermentation assay, phenol red, in the presence of neutral pH?

Answer 249

It remains red

Question 250

What color does the carbohydrate fermentation assay, phenol red, turn in the presence of acidic pH?

Answer 250

Yellow

Question 251

When the carbohydrate fermentation assay, phenol red, turns yellow, what does that indicate?

Answer 251

Acidic pH

Question 252

What is an overturned Durham tube used as a carbohydrate fermentation assay an indication of?

Answer 252

Gas

Question 253

How is gas indicated in the carbohydrate fermentation assay called the overturned Durham tube?

Answer 253

The overturned Durham tube with no gas production will have medium in the tube, whereby with gas production, there will be an air bubble.

Question 254

What are the four possible results to a carbohydrate fermentation assay?

Answer 254

1. No fermentation
2. Acid only
3. Gas only
4. Acid and gas

Question 255

What are the color outcomes of phenol red as a carbohydrate fermentation assay on these four possible results?

1. No fermentation - red
2. Acid only - yellow
3. Gas only - red
4. Acid and gas - yellow

Question 256

What are the outcomes of the overturned Durham tube to these carbohydrate fermentation assays?

1. No fermentation - no bubble
2. Acid only - no bubble
3. Gas only - bubble
4. Acid and gas - bubble

Question 257

How does fermentation allow the MRVP test to distinguish between Escherichia coli and Enterobacter cloacae?

Answer 257

MR (Methyl Red) and VP (Voges-Proskauer test)

Escherichia coli and Enterobacter cloacae are two very similar types of bacteria and the MRVP test helps distinguish between the two.

• MR is a pH indicator:
  
  • E. coli fermentation produces acids with a pH of 4.5 or lower. Methyl red turns red at this pH.
  • Enterobacter do not produce many acids so the pH is higher. Methyl red stays yellow at this pH.
• VP tests for the presence of acetoin in media:
  
  • E. coli does not form acetoin. VP will be light bron/yellow.
  • Enterobacter forms acetoin. The media will turn red/pink (often in a rim around the surface of the culture).

Question 258

What two microorganisms is the MRVP test used to distinguish?

Answer 258

Escherichia coli and Enterobacter cloacae

Question 259

What tests make up the MRVP test?

Answer 259

Methyl Red and Voges-Proskauer tests

Question 260

What does the MRVP test do?

Answer 260

Differentiates between Escherichia coli and Enterbactor cloacae?

Question 261

How is the MRVP test able to differentiate between Escherichia coli and Enterobactor cloacae?

Answer 261

• E. coli* fermentation produces acids with a pH of 4.5 or lower. Methyl red turns red at this pH.
• Enterobacter* do not produce many acids so the pH is higher. Methyl red stays yellow at this pH.
• E. coli* does not form acetoin. VP will be light brown/yellow.
• Enterobacter* forms acetoin. The media will turn red/pink (often in a rim around the surface of the culture).

Question 262

How can the MRVP test differentiate between Escherichia coli and Enterobacter cloacoa?

Answer 262

E. coli fermentation:

• produces acids, dropping pH to 4.5 to cause methyl red to turn red
• does not produce acetoin so Voges-Proskauer is light brown/yellow

Enterobacter cloacae:

• doesn’t produce acids so methyl red turns yellow
• produces acetoin so Voges-Proskauer will turn red/pink with a ring around the surface

Question 263

Which bacteria tested with the MRVP test produces acetoin?

Answer 263

Enterobacter cloacae

Question 264

Which bacteria produces acids that show on the MRVP test?

Answer 264

Echerichia coli

Question 265

Choose the right option

Enterobacter cloacae produce (acid/acetoin) which will turn the (methyl red/Voges-Proskauer) test (yellow or red/pink with ring)?

Answer 265

Enterobacter cloacae produce acetoin which will turn the Voges-Proskauer test red/pink with ring?

Question 266

Escherichia coli produce (acid/acetoin) which will turn the (methyl red/Voges-Proskauer) test (yellow or red)?

Answer 266

Escherichia coli produce acids which will turn the methyl red test red.

Question 267

What are the starting molecules in each cycle of aerobic cellular respiration?

Answer 267

Glycolysis - glucose (6-carbon molecule - initial electron donor)

Decarboxylation and the Krebs Cycle - 2 pyruvic acids (2 carbons each from glycolysis)

Oxidative phosphorylation - none

Question 268

What are the ending molecules in each cycle of aerobic cellular respiration?

Answer 268

Glycolysis - 2 pyruvic acids (3 carbons each)

Decarboxylation and the Krebs Cycle - 6 CO₂

Oxidative phosphorylation - none

Question 269

What are the starting and ending ATP or ADP + Pi numbers in each cycle of aerobic cellular respiration?

Answer 269

Glycolysis

• Starting: 2 ATP and 4 ADP + Pi
• Ending: 2 ADP + 2 Pi and 4 ATP (net 2 ATP)

Decarboxylation and Krebs Cycle

• Starting: 2 ADP + 2 Pi
• Ending: 2 ATP

Oxidative phosphorylation

• Starting: 34 ADP + Pi
• Ending: 34 ATP

Question 270

What are the starting and ending electron carriers in all three stages of aerobic cellular respiration?

Answer 270

Glycolysis

• Starting: 2 NAD⁺ + 2 H⁺
• Ending: 2 NADH

Decarboxylation and the Krebs Cycle

• Starting: 8 NAD⁺ + 8 H⁺ and 2 FAD + 4 H^+​
• Ending: 8 NADH and 2 FADH₂

Oxidative phosphorylation

• Starting: 10 NADH and 2 FADH2 (from glycolysis and decarb/Krebs)
• Ending: 10 NAD⁺ + 10 H⁺ and 2 FAD + 4 H⁺ (oxidized)

Question 271

What are the starting O₂ or H₂O molecules in all three segments of aerobic cellular respiration?

Answer 271

Glycolysis

• Starting: none
• Ending: none

Decarboxylation and the Krebs Cycle

• Starting: none
• Ending: none

Oxidative phosphorylation

• Starting: 6 O₂ + 24 H⁺
• Ending: 12 H₂O (reduced - final electron acceptor)

Question 272

What are the intial electron donor and the final electron acceptor in aerobic cellular respiration and in which of the three processes do they occur?

Answer 272

Glucose, C₆H₁₂O₆, a 6-carbon molecule, is the initial electron donor in glycolysis.

H₂O is the final electron acceptor in oxidative phosphorylation.

Question 273

Where does carbon dioxide come in during aerobic cellular respiration and what role does it play?

Answer 273

Six carbon dioxide molecules (6 CO₂) are the ending organic molecules in decarboxylation and the Krebs Cycle.

Question 274

What are the electron carriers involved in aerobic cellular respiration and in what processes do they appear?

Answer 274

Glycolysis

• 2 NAD⁺ + 2H⁺ –> 2 NADH

Decarboxylation and the Krebs Cycle

• 8 NAD⁺ + 8 H⁺ –> 8 NADH
• 2 FAD + 4 H⁺ –> 2 FADH₂

Oxidative phosphorylation

• 10 NADH (from 1st 2 pathways) –> 10 NAD⁺ + 10 H⁺
• 2 FADH2 (from 1st 2 pathways) –> 2 FAD + 4 H⁺

Question 275

What is the final electron acceptor in aerobic cellular respiration and is it oxidized or reduced?

Answer 275

H₂O, reduced

Question 276

How many ADP + Pi and ATP are used and produced in aerobic cellular respiration?

Answer 276

Glycolysis (net 2 ATP)

• 2 ATP –> 2 ADP + 2 Pi
• 4 ADP + Pi –> 4 ATP

Decarboxylation and the Krebs Cycle

• 2 ADP + P_i –> 2 ATP

Oxidative phosphorylation

• 34 ADP + 34 Pi –> 34 ATP

Question 277

What molecule is the first reactant in the Krebs Cycle?

Answer 277

Two 3-carbon pyruvic acids

Question 278

What is the last molecule produced in glycolysis?

Answer 278

Two 3-carbon pyruvic acids

Question 279

What are two other names for the Krebs Cycle?

Answer 279

Tricarboxylic acid cycle or TCA cycle

Question 280

T/F

The tricarboxylic acid cycle occurs only once per glucose molecule.

Answer 280

False.

The tricarboxylic acid cycle (TCA) or the Krebs Cycle cycles once for each 3-carbon pyruvid acid molecules, both of which result from a single glucose molecule. In other words, the tricarboxylic acid cycle cylces twice for each glucose molecule.

Question 281

What is the summary of molecules resulting from the TCA cycle and are they reduced or oxidized?

Answer 281

• 2 pyruvic acids (from glycolysis) oxidized to 6 CO₂ which leave the reaction
• 8 NAD⁺ + H⁺ reduced to NADH
• 2 FAD + 4 H⁺ reduced to FADH₂
• 2 ADP + Pi make 2 ATP

Question 282

Are the electron carriers reduced or oxidized in each of the processes of glycolysis, TCA cycle and oxidative phosphorylation?

Answer 282

Glycolysis:

• 2 NAD⁺ + 2 H⁺ reduced to NADH

Tricarboxylic acid cycle

• 8 NAD⁺ + 8 H⁺ reduced to 8 NADH
• 2 FAD + 4 H⁺ reduced to 2 FADH₂

Oxidative phosphorylation (the oxidation is needed to release H+ ions to the electron transport cycle)

• 10 NADH oxidized to 10 NAD⁺ + 10 H⁺
• 2 FADH₂ oxidized to 2 FAD + 4 H⁺

Question 283

What electron carrier that’s used in aerobic cellular respiration is not used in fermentation?

Answer 283

FADH₂

Question 284

Each glucose molecule that enters fermentation will go through what process that aerobic cellular respiration uses?

Answer 284

Glycolysis

Question 285

Which process does aerobic cellular respiration have in common with fermentation?

Answer 285

Glycolysis

Question 286

Glycolysis is a process of fermentation that is has in common with which other metabolic pathway?

Answer 286

Aerobic cellular respiration

Question 287

Each glucose molecule that enters fermentation will go through glycolysis and what else?

Answer 287

One secondary fermentation reaction like lactic acid, ethanol or another.

Question 288

Glycolysis produces what molecules that enter into secondary fermentation reactions?

Answer 288

Two 3-carbon pyruvic acids molecules

Question 289

What do the two 3-carbon pyruvic acids from glycolsis reduce to in lactic acid fermentation?

Answer 289

Two 3-carbon lactic acid molecules

Question 290

What do the two 3-carbon pyruvic acid molecules reduce to in ethanol fermentation?

Answer 290

Two 2-carbon ethanols + 2 CO₂

Question 291

What are the final electron acceptors in lactic acid fermentation and ethanol fermentation?

Answer 291

Two 3-carbon lactic acids in lactic acid fermentation

Two 2-carbon ethanols + 2 CO₂ in ethanol fermentation

Question 292

What are the starting and ending electron carriers in fermentation?

Answer 292

2 NADH (from glycolysis) oxidized to 2 NAD⁺ + 2 H⁺ for both lactic acid and ethanol fermentation.

Question 293

What are the numbers of starting and ending ATP/ADP + Pi in fermentation and from what process do they come?

Answer 293

2 ATP –> 2 ADP + 2 Pi

4 ADP + 4 Pi –> 4 ATP

(net 2 ATP)

Produced in glycolysis

Question 294

What are the starting and ending ATP/ADP + Pi molecules in the secondary fermentation reactions of fermentation?

Answer 294

Zero

Question 295

What are the starting and ending O₂ and H_2O molecules in fermentation?

Answer 295

Zero

Question 296

What are the electron carriers in the two stages of fermentation?

Answer 296

Glycolysis:

• 2 NAD⁺ + 2 H⁺ –> 2 NADH

Secondary fermentation reaction (lactic acid or ethanol)

• 2 NADH (from glycolysis) oxidized to 2 NAD⁺ + 2 H⁺

Question 297

What is the ending electron carrier in glycolysis and is it reduced or oxidized?

Answer 297

2 NADH, reduced

Question 298

How many ATPs result from fermentation and in what process are they produced?

Answer 298

2 ATPs, glycolysis

Question 299

What is the summary of the chemical reaction of photosynthesis found in plants, algae and cyanobacteria? In other words, the photosynthentic process that uses H₂O as an electron donor.

Answer 299

6CO₂ + 6 H₂O + (light energy) —> C₆H₁₂O₆ + 6O₂

Question 300

In photosynthesis found in plants, algae and cyanobacteria, what is the electron donor?

Answer 300

H₂O

Question 301

The photosynthesis that uses H2O as the electron donor is used in what three types of organisms?

Answer 301

Plants, algae and cyanobacteria

Question 302

Plants, algae and cyanobacteria use what type of metabolic process and what is the electron donor in that process?

Answer 302

Photosynthesis, H₂O

Question 303

Is photosynthesis and anabolic or catabolic process?

Answer 303

Anabolic

Question 304

What is the electron donor in photosynthesis and is it oxidized or reduced?

Answer 304

H₂O, oxidized (releases O₂)

Question 305

What are the 2 steps in photosynthesis?

Answer 305

Light-dependent and light-independent (Calvin cycle).

Question 306

Light-dependent and light-independent (Calvin cycle) are the names of what?

Answer 306

The 2 steps in photosynthesis.

Question 307

What is another name for the Calvin cycle?

Answer 307

Light-independent step in photosynthesis

Question 308

What do the light-dependent reactions in photosynthesis produce and what is dependent on these products?

Answer 308

Produces ATP, NADPH and O₂ from ADP + Pi, NADP⁺ + H⁺ and H₂O.

The light-independent step (Calvin cycle) is dependent on the products from the light-dependent reactions.

Question 309

Produces ATP, NADPH and O₂ from ADP + Pi, NADP⁺ + H⁺ and H₂O.

Answer 309

Light-dependent reaction of photosynthesis

Question 310

The light-independent step (Calvin cycle) is dependent on the products from what other step?

Answer 310

From the light-dependent step that produces ATP, NADPH and O₂ from ADP + Pi, NADP⁺ + H⁺ and H₂O

Question 311

What does the light-independent reaction in photosynthesis produce?

Answer 311

Three 3-carbon molecules (Glycerol 3-phosphate or G3P) that can be used to make glucose (and other molecules)

Question 312

Glycerol-3-phosphate is produced by what metabolic process and what is it used for?

Answer 312

The light-independent reaction (the 2nd step) in photosynthesis

Used to make glucose and other molecules

Question 313

In the light-independent reaction in photosynthesis, what is created per 1 glucose (2 G3Ps)?

Answer 313

18 ATP to 18 ADP + Pi and

12 NADPH into 12 NADP⁺ + 12 H⁺

Question 314

What is required to convert

• 18 ATP to 18 ADP + Pi and
• 12 NADPH into 12 NADP⁺ + 12 H⁺

and in what metabolic process does this occur?

Answer 314

1 glucose (2 G3P)

Light-independent reaction in photosynthesis

Question 315

What are the products of the two reactions in photosynthesis?

Answer 315

Light-dependent: ATP, NADPH, O₂

Light-independent (Calvin cycle): 18 ADP + Pi, 12 NADP⁺ + H⁺ per glucose

Question 316

What part of photosynthesis has these products and what are they produced from?

ATP

NADPH

O2

Answer 316

Light-dependent

ADP + Pi

NADP⁺ + H⁺

H₂O

Question 317

What are the products of light-independent (Calvin cycle) part of photosynthesis and what are they produced from?

Answer 317

Three 3-carbon molecules (Glycerol-3-phosphate (G3P) that are used to make glucose and other molecules.

The light-independent reaction also convert per glucose:

18 ATP to 18 ADP + Pi

12 NADPH to 12 NADP+ + H+

Question 318

In what part of photosynthesis is this converted?

18 ATP to 18 ADP + Pi

Answer 318

Light-independent reaction

Question 319

In what part of photosynthesis is this converted?

ADP + Pi to ATP

Answer 319

Light-dependent

Question 320

In what part of photosynthesis is this converted?

12 NADPH to 12 NADP⁺ + H⁺

Answer 320

Light-independent

Question 321

In what part of photosynthesis is this conversion taking place?

18 ATP to 18 ADP + Pi

Answer 321

Light-independent

Question 322

How are the light-dependendent and light-independent reactions in photosynthesis linked?

Answer 322

The ATP and NADPH from the light-dependent reactions are needed to provide chemical energy and high energy electrons to the light-independent reactions.

Question 323

What 2 molecules from the light-dependent reactions are needed to provide chemical energy and high energy electrons to the light-independent reactions.

Answer 323

ATP and NADPH

Question 324

ATP and NADPH from the light-dependent reactions provide the light-independent reactions with high energy electrons that are used how?

Answer 324

Reducing power.

Question 325

Reducing power is provided to the light-independent reactions through what molecules?

Answer 325

High energy electrons

Question 326

How is the ATP generated in catabolism used in anabolism?

Answer 326

The ATP generated in catabolism (light-dependent) provides chemical energy to construct more complicated molecules in anabolism. The molecules made in anabolism (light-independent) are eventually used to allow the cell to divide (reproduce).

Question 327

What is an amphibolic pathway?

Answer 327

Amphibolic pathways are dual-purpose pathways that function in both anabolism and catabolism. Intermediates shared between reactions can be used for either reaction.

Question 328

What is this describing?

Dual-purpose pathways that function in both anabolism and catabolism.

Answer 328

Amphibolic pathways

Question 329

What is this describing?

Pathways with intermediates that are shared between reactions and can be used for either reaction.

Answer 329

Amphibolic pathways

Question 330

What is an example of an amphibolic pathway?

Answer 330

The Krebs cycle (Citric acid cycle)

Question 331

What are the roles that aerobic respiration, anaerobic respiration and fermentation play in the carbon cycle?

Answer 331

In the carbon cycle…

Larger carbon molecules are broken down into:

1. Aerobic respiration - to CO₂ (complete breakdown)
2. Anerobic respiration - to CO₂ (complete breakdown)
3. Fermentation - some fermentation reactions produce ethonol (2 carbons) and one CO₂ (partial breakdown)

CO₂ is fixed and converted into larger carbon molecules in:

1. Photosynthesis

Question 332

What is the role of aerobic respiration, anaerobic respiration, fermentation and photosynthesis in the oxygen cycle?

Answer 332

In the oxygen cycle…

O₂ is converted to H₂O in:

1. Aerobic respiration - O₂ is converted to H₂O. Where O₂ acts as the final electron acceptor and is reduced to H₂O.

H₂O is converted into O₂ in:

1. Photosynthesis - (oxygenic only) H₂O is used as the initial electron donor and is oxidized to O₂.

Question 333

What is the role of aerobic respiration, anaerobic respiration, fermentation and photosynthesis in the nitrogen cycle?

Answer 333

In the nitrogen cycle…

Nitrogen containing molecules are broken down on their way to:

1. Aerobic respiration
2. Anaerobic respiration
3. Fermentation

Ammonia (NH₄) and other nitrogen-containing compounds (NO₃, NO₂, NO, N₂O) are reduced to gaseous nitrogen (N₂) in:

1. Anaerobic respiration where the nitrogen-containing compounds are used as a final electron acceptor and are reduced to N₂.

Nitrogen fixation (conversion of N₂ to NH₄) is an anabolic reaction (requires a large amount of ATP) that is perfomed by soil bacteria and bacteria that are symbiotic with legumes, such as species of Rhizobium.

Question 334

In the nitrogen cycle, nitrogen containing molecules are broken down on their way to which three types of metabolism?

Answer 334

Aerobic, anaerobic and fermentation

Question 335

Ammonia (NH4) and other nitrogen-containing compounds (NO3, NO2, NO, N2O) are reduced to gaseous nitrogen (N2) in what metabolic processes?

Answer 335

Anaerobic respiration. This is where nitrogen-containing compounds are used as a final electron acceptor and are reduced to N₂.

Question 336

Nitrogen fixation (conversion of N₂ to NH₄ (ammonia)) is an anabolic reaction (requires a large amount of ATP) that is performed by what?

Answer 336

Soil bacteria and bacteria that are symbiotic with legumes, such as species of Rhizobium.

Question 337

In the carbon cycle, larger carbon molecules are broken down in what metabolic processes?

Answer 337

1. Aerobic respiration - to CO₂ (complete breakdown)
2. Anerobic respiration - to CO₂ (complete breakdown)
3. Fermentation - some fermentation reactions produce ethonol (2 carbons) and one CO₂ (partial breakdown)

Question 338

In what metabolic processes is CO₂ fixed and converted into larger carbon molecules?

Answer 338

Photosynthesis only

Question 339

In the oxygen cycle, O₂ is converted to H₂O in what metabolic processes?

Answer 339

Aerobic respiration.

O₂ is the final electron acceptor and is reduced to H₂O.

Question 340

In the oxygen cycle, H₂O is converted to O₂ in which metabolic process?

Answer 340

Photosynthesis (oxygenic only).

H₂O is used as the initial electron donor and is oxidized to O₂.

Question 341

Which metabolic pathways are involved in the carbon cycle?

Answer 341

1. Larger carbon molecules are broken down in aerobic and anaerobic cellular respiration and some fermentation.
2. CO₂ is fixed and converted into large carbon molecules in Photosynthesis.

Question 342

Aerobic cellular respiration, anaerobic cellular respiration, fermentation and photosynthesis are all involved in what biogeochemical cycle?

Answer 342

Carbon cycle

Question 343

Aerobic cellular respiration and photosynthesis are the only two metabolic processes required to complete out what biogeochemical cycle?

Answer 343

Oxygen cycle

Question 344

In what biogeochemical cycle are aerobic respiration, anaerobic respiration, fermentation and soil bacteria required to complete the cycle?

Answer 344

Nitrogen cycle

Question 345

What three metabolic processes are involved in breaking down molecules in the carbon cycle and the nitrogen cycle?

Answer 345

Aerobic respiration, anaerobic respiration and fermentation.

Question 346

What are larger carbon molecules broken down to in the carbon cycle?

Answer 346

CO₂

Question 347

What are the two molecules involved in the oxygen cycle?

Answer 347

O₂ and H₂O

Question 348

In the oxygen cycle, O₂ is converted to H₂O in what metabolic pathway and is O₂ oxidized or reduced to H₂O?

Answer 348

Aerobic cellular respiration

Reduced

Question 349

In the oxygen cycle, H₂O is used as the initial electron donor by what metabolic pathway?

Is H₂O oxidized or reduced to O₂?

Answer 349

Photosynthesis

Oxidized

Question 350

What is required by the light-dependent reaction?

In what metabolic pathway is this present?

Answer 350

Light energy is required

Photosynthesis

Question 351

What are the starting and ending organic molecules in light-dependent reactions?

Answer 351

There are none

Question 352

What are the starting ATP/ADP + Pi needed in light-dependent reactions?

Answer 352

Starting ADP + Pi

Ending ATP

Question 353

What are the starting and ending electron carriers in light-dependent reactions?

Answer 353

Starting NADP⁺ + H⁺

Ending NADPH (reduced)

Question 354

What are the starting and ending molecules in light-dependent reactions?

Answer 354

Starting: H₂O (electron donor)

Ending: O₂ (oxidized)

Question 355

What are the starting and ending molecules in light-independent reactions?

Answer 355

Starting: 6 CO₂

Ending: 1 glucose (C₆H₁₂O₆) (Reduced)

Question 356

What are the starting and ending ATP/ADP + Pi in light-independent reactions?

Answer 356

Starting: 18 ATP (from light-dependent)

Ending: 18 ADP + Pi

Question 357

What are the starting and ending electron carriers in light-independent reactions?

Answer 357

Starting: 12 NADPH (from light-dependent reaction)

Ending: 12 NADP⁺ + H⁺ (oxidized)

Question 358

What are the starting and ending O₂ or H₂O molecules in light-independent reactions?

Answer 358

There are none.

Question 359

How are ATP and ADP + Pi used in light-dependent and light-independent reactions?

Answer 359

Light-dependent:

• Starting ADP + Pi
• Ending ATP

Light-independent:

• Starting 18 ATP
• Ending 18 ADP + Pi

Question 360

How are electron carriers moved between light-dependent and light-independent reactions?

Answer 360

Light-dependent:

• Starting NADP⁺ + H⁺
• Ending NADPH (reduced)

Light-independent

• Starting NADPH (from light-dependent reaction)
• Ending NADP⁺ + H⁺ (oxidized)

Question 361

List the classifications of bacteria based on temperature.

Answer 361

1. Psychrophiles: cold-loving (between -5°C and 30°C)
   
   1. Psychotroph: organisms that grow slowly at 0°C but still grow well at room temp (often cause spoilage)
2. Mesophiles: moderate-temperature loving (20°C - 45° C)
3. Thermophiles: heat-loving (> 45°C)
   
   1. Hyperthermophiles (usually > 80°C)

Question 362

List classification of bacteria based on pH.

Answer 362

• Acidophiles - grow in more acidic environments
• Neutrophiles - grow in neutral environments
• Alkaliphiles - grow in basic environments

Question 363

List classifications of bacteria based on osmotic pressure.

Answer 363

• Extreme halophiles - well-adapated to high salt concentrations
• Obligate halophiles - require high salt concentrations to grow
• Facultative halophiles - do not require high salt concentrations but are able to grow in concentrations of 2%

Question 364

Which defines the term below:

Psychrophiles

1. Cold loving (-5°C to 30°C)
2. Moderate-loving (20°C to 45°C)
3. Grow slowly at 0°C and grow well at room temp
4. Heat-loving (> 45°C)
5. Live at very high temps (> 80°C)

Answer 364

Psychrophiles = 1. Cold-loving (-5°C to 30°C)

Question 365

Which defines the term below:

Mesophiles

1. Cold loving (-5°C to 30°C)
2. Moderate-loving (20°C to 45°C)
3. Grow slowly at 0°C and grow well at room temp
4. Heat-loving (> 45°C)
5. Live at very high temps (> 80°C)

Answer 365

Mesophiles = 2. Moderate loving (20°C to 45°C)

Question 366

Which defines the term below:

Thermophiles

1. Cold loving (-5°C to 30°C)
2. Moderate-loving (20°C to 45°C)
3. Grow slowly at 0°C and grow well at room temp
4. Heat-loving (> 45°C)
5. Live at very high temps (> 80°C)

Answer 366

Thermophiles = 4. Heat-loving (> 45°C)

Question 367

Which defines the term below:

Psychotroph

1. Cold loving (-5°C to 30°C)
2. Moderate-loving (20°C to 45°C)
3. Grow slowly at 0°C and grow well at room temp
4. Heat-loving (> 45°C)
5. Live at very high temps (> 80°C)

Answer 367

Psychotroph = 3. Grow slowly at 0°C and grow well at room temp

Question 368

Which defines the term below:

Hyperthermophiles

1. Cold loving (-5°C to 30°C)
2. Moderate-loving (20°C to 45°C)
3. Grow slowly at 0°C and grow well at room temp
4. Heat-loving (> 45°C)
5. Live at very high temps (> 80°C)

Answer 368

Hyperthermophiles = 5. Live at very high temps (> 80°C)

Question 369

Which organism grows above 80°C?

Answer 369

Hyperthermophile

Question 370

Which organism grows slowly at 0°C but will grow well at room temperature and is responsible for spoilage?

Answer 370

Pyschotrophs

Question 371

Which organisms grows above 45°C and are heat-loving?

Answer 371

Thermophiles

Question 372

Which organisms love moderate temps (20°C to 45°C)?

Answer 372

Mesophiles

Question 373

Which organisms are cold-loving (-5°C to 30°C)?

Answer 373

Psychrophiles

Question 374

Match the organism with the definition.

Acidophiles

1. Grow in acidic environments
2. Grow in neutral pH environments
3. Grow in basic environments

Answer 374

Acidophiles = 1. Grow in acidic environments

Question 375

Match the organism with the definition.

Neutrophiles

1. Grow in acidic environments
2. Grow in neutral pH environments
3. Grow in basic environments

Answer 375

Neutrophiles = 2. Grow in neutral pH environments

Question 376

Match the organism with the definition.

Alkaliphile

1. Grow in acidic environments
2. Grow in neutral pH environments
3. Grow in basic environments

Answer 376

Alkaliphile: 3. Grow in basic environments

Question 377

Which organisms grow in a basic pH environment?

Answer 377

Alkaliphiles

Question 378

Which organisms grow in an acidic pH?

Answer 378

Acidophiles

Question 379

Which organisms grow best in neutral pH environments?

Answer 379

Neutrophiles

Question 380

Match the organism to the definition:

Extreme halophile

1. Well-adapted to high salt concentrations
2. Require high salt concentrations to grow
3. Do not require high salt concentrations but are able to grow at 2% concentrations

Answer 380

Extreme halophile = 1. Well-adapted to high salt concentrations

Question 381

Match the organism to the definition:

Obligate halophile

1. Well-adapted to high salt concentrations
2. Require high salt concentrations to grow
3. Do not require high salt concentrations but are able to grow at 2% concentrations

Answer 381

Obligate halophile = 2. Require high salt concentrations to grow

Question 382

Match the organism to the definition:

Facultative halophile

1. Well-adapted to high salt concentrations
2. Require high salt concentrations to grow
3. Do not require high salt concentrations but are able to grow at 2% concentrations

Answer 382

Facultative halophile = 3. Do not require high salt concentrations but are able to grow at 2% concentrations

Question 383

Psychrophiles, mesophiles, thermophiles, psychotrophs and hyperthermophiles are terms classifying microbes based on what?

Answer 383

Temperature

Question 384

Acidophiles, neutrophiles and alkaliphiles are organisms classified by what?

Answer 384

pH tolerance

Question 385

Extreme halophiles, obligate halophiles and facultative halophiles are classifications of organisms based on what characteristic?

Answer 385

The salt concentration preferred to grow

Question 386

This element is the structural backbone of most living matter and is used to make all of the macromolecules in the cell.

Answer 386

Carbon

Question 387

Half of the dry weight of a cell is composed of what element?

Answer 387

Carbon

Question 388

Carbon composes what percent of dry weight of a cell?

Answer 388

50%

Question 389

What element is required to make all macromolecules in a cell?

Answer 389

Carbon

Question 390

Carbon is the _________ ________ of most living matter.

Answer 390

Structural backbone

Question 391

What element is added to media as organic molecules, often in the form of carbohydrates or protein?

Answer 391

Carbon

Question 392

Most bacteria get what element by decomposing amino acids?

Answer 392

Nitrogen

Question 393

Some bacteria are able to use ammonia as a source of what element?

Answer 393

Nitrogen

Question 394

Some bacteria are able to use gaseous nitrogen from the atmosphere in a process called what?

Answer 394

Nitrogen fixation

Question 395

Bacteria are able to get a source of nitrogen from what three sources?

Answer 395

1. Decomposing amino acids
2. Using ammonia
3. Nitrogen fixation (from gaseous nitrogen in the air)

Question 396

What element is necessary to have in growth media for the synthesis of amino acids and nucleotides?

Answer 396

Nitrogen

Question 397

Amino acids are important in a growth medium for the synthesis of what?

Answer 397

Proteins

Question 398

Nitrogen in growth medium is important to make nucleotides to make what?

Answer 398

Nucleic acids

Question 399

Synthesis of proteins and nucleic acids can be facilitated by adding what to growth media and what are the sources of it?

Answer 399

Nitrogen

Decomposing amino acids, ammonia or nitrogen fixation

Question 400

Why is sulfur necessary in growth media?

Answer 400

Is always added to synthesize sulfur-containing amino acids (methionine, cystine)

Question 401

What element is provided in growth media by adding sulfate ions, hydrogen sulfide or sulfur-containing amino acids?

Answer 401

Sulfur

Question 402

Sulfur-containing amino acids can only be synthesized if what is added to the growth media?

Answer 402

Sulfur

Question 403

Phosphorus is often obtained as phosphate ions and is used to make nucleotides and lipids in what?

Answer 403

Growth media

Question 404

Growth media requires what to make nucleotides and lipids?

Answer 404

Phosphorus

Question 405

List the four elements required in growth media.

Answer 405

1. Carbon
2. Nitrogen
3. Sulfur
4. Phosphorus

Question 406

List the four elements required in growth media and what macromolecule requires that element.

Answer 406

1. Carbon - all macromolecules
2. Nitrogen - amino acids and nucleotides
3. Sulfur - Sulfur-containing amino acids
4. Phosphorus - nucleotides and lipids

Question 407

Of the elements required in growth media, which one is required by all macromolecules?

Answer 407

Carbon

Question 408

Of the four elements required in a growth medium, which one is required for sulfur-containing amino acids?

Answer 408

Sulfur

Question 409

Of the four elements required for growth media, which ones are required for nucleotides?

Answer 409

Nitrogen and phosphorus

Question 410

Of the four elements required for growth media, which one is necessary for amino acids and nucleotides?

Answer 410

Nitrogen

Question 411

Of the four elements required for growth media, which one is necessary for the synthesis of nucleotides and lipids?

Answer 411

Phosphorus

Question 412

What is FTM and why is it useful as a growth medium?

Answer 412

Fluid thioglycolate medium is useful because thioglycolate is a reducing agent which means it reduces O₂ to H₂O (oxidizing the thioglycolate) to create an O₂ free medium. However, it can only reduce the molecule once. Then O₂ in the medium will be higher in the areas exposed to O2 like the top of a tube. This supports growth of organisms that have the enzymes to protect it from high O2 environments for purposes of differentiation.

Question 413

O₂ concentrations in a tube of FTM will be lowest where?

Answer 413

At the bottom

Question 414

O₂ concentration in a tube of FTM will be highest where?

Answer 414

At the top

Question 415

What happens to O2 concentration as you move from the top to the bottom in a FTM-filled tube?

Answer 415

O₂ concentrations decrease from top to bottom.

Question 416

In an FTM tube, fast microorganism growth requires what metabolic pathway?

Answer 416

Aerobic cellular respiration

Question 417

In an FTM tube, slow growth will occur when cells ar using what two types of metabolism?

Answer 417

Anaerobic cellular respiration or fermentation to make ATP

Question 418

Obligate aerobes are capable of aerobic cellular respiration

(Yes/No)

Answer 418

Yes

Question 419

Obligate anaerobes are capable of aerobic cellular respiration

(Yes/No)

Answer 419

No

Question 420

Aerotolerant anaerobes are capable of aerobic cellular respiration

(Yes/No)

Answer 420

No

Question 421

Facultative anaerobes are capable of aerobic cellular respiration

(Yes/No)

Answer 421

Yes

Question 422

Microaerophiles are capable of aerobic cellular respiration

(Yes/No)

Answer 422

Yes

Question 423

Obligate aerobes are capable of anaerobic cellular respiration and/or fermentation.

(Yes/No)

Answer 423

No

Question 424

Obligate anaerobes are capable of anaerobic cellular respiration and/or fermentation.

(Yes/No)

Answer 424

Yes

Question 425

Aerotolerant anaerobes are capable of anaerobic cellular respiration and/or fermentation.

(Yes/No)

Answer 425

Yes

Question 426

Facultative anaerobes are capable of anaerobic cellular respiration and/or fermentation.

(Yes/No)

Answer 426

Yes

Question 427

Microaerophile are capable of anaerobic cellular respiration and/or fermentation.

(Yes/No)

Answer 427

No

Question 428

Obligate aerobes make enzymes that detoxfy oxygen.

(Yes/No)

Answer 428

Yes

Question 429

Obligate anaerobes make enzymes that detoxfy oxygen.

(Yes/No)

Answer 429

No

Question 430

Aerotolerant anaerobes make enzymes that detoxfy oxygen.

(Yes/No)

Answer 430

Yes

Question 431

Facultative anaerobes make enzymes that detoxfy oxygen.

(Yes/No)

Answer 431

Yes

Question 432

Microaerophiles make enzymes that detoxify oxygen.

(Yes/No)

Answer 432

No

Question 433

Obligate aerobes growth at the top of an FTM tube

(Fast/Slow/No)

Answer 433

Fast

Question 434

Obligate anaerobes growth at the top of an FTM tube

(Fast/Slow/No)

Answer 434

No

Question 435

Aerotolerant anaerobes growth at the top of an FTM tube

(Fast/Slow/No)

Answer 435

Slow

Question 436

Facultative anaerobes growth at the top of an FTM tube

(Fast/Slow/No)

Answer 436

Fast

Question 437

Microaerophiles growth at the top of an FTM tube

(Fast/Slow/No)

Answer 437

No

Question 438

Obligate aerobe growth at the middle of the tube

(Fast/Slow/No)

Answer 438

No

Question 439

Obligate anaerobe growth at the middle of the tube

(Fast/Slow/No)

Answer 439

No/Slow

Question 440

Aerotolerant anaerobe growth at the middle of the tube

(Fast/Slow/No)

Answer 440

Slow

Question 441

Facultative anaerobe growth at the middle of the tube

(Fast/Slow/No)

Answer 441

Slow

Question 442

Microaerophile growth at the middle of the tube

(Fast/Slow/No)

Answer 442

Fast

Question 443

Obligate aerobe growth at the bottom of the FTM tube

(Fast/Slow/No)

Answer 443

No

Question 444

Obligate anaerobe growth at the bottom of the FTM tube

(Fast/Slow/No)

Answer 444

Slow

Question 445

Aerotolerant anaerobe growth at the bottom of the FTM tube

(Fast/Slow/No)

Answer 445

Slow

Question 446

Facultative anaerobe growth at the bottom of the FTM tube

(Fast/Slow/No)

Answer 446

Slow

Question 447

Microaerophile growth at the bottom of the FTM tube

(Fast/Slow/No)

Answer 447

No

Question 449

What does the growth pattern in a tube look like for an obligate aerobe?

Answer 449

Question 450

What does the growth pattern in a tube look like for an obligate anaerobe?

Answer 450

Question 451

What does the growth pattern in a tube look like for an aerotolerant anaerobe?

Answer 451

Question 452

What does the growth pattern in a tube look like for a facultative anaerobe?

Answer 452

Question 453

What does the growth pattern in a tube look like for a microaerophile?

Answer 453

Question 454

What two contributions came from members of Robert Koch’s laboratory to the culture of microorganisms?

Answer 454

• Fannie Hesse, tech for her husband in the lab, suggested agar (used in jam) for an effective setting agent.
• Robert Petri invented the streak plate method for isolating pure colonies and the plate that bears his name.

Question 455

Who is Fannie Hesse?

Answer 455

A tech in Robert Koch’s lab who suggested the use of agar as an effective setting agent.

Question 456

What did Fannie Hesse suggest as an effective setting agent in Robert Koch’s lab?

Answer 456

Agar

Question 457

What did Robert Petri invent?

Answer 457

The streak plate method and the dish that bears his name.

Question 458

What is the streak plate method used for?

Answer 458

Isolating pure cultures

Question 459

What is chemically defined media?

Answer 459

Used when the exact chemical composition is known and is useful for experimental testing of requirements for growth and for growing fastidious (picky) organisms.

Question 460

What type of media is used when the exact chemical composition is known.

Answer 460

Chemically defined media

Question 461

What type of media is useful for experimental testing of requirements for growth and for growing fastidious (picky) organisms.

Answer 461

Chemically defined media

Question 462

What is complex (undefined) media?

Answer 462

• Media where the exact chemical composition is unknown
• Complex medias are usually made from nutrients including extracts from yeasts, meat, plants or digests of proteins from other sources
• Complex medias are useful for growing bacteria inexpensively

Question 463

Which type of media is the one where the exact chemical composition is unknown?

Answer 463

Complex (undefined) media

Question 464

Which type of media is usually made from nutrients including extracts from yeasts, meat, plants or digests of proteins from other sources?

Answer 464

Complex (undefined) media

Question 465

Which type of media is useful for growing bacteria inexpensively?

Answer 465

Complex (undefined) media

Question 466

Which type of media is used for growing bacteria inexpensively and which one is good for growing fastidious organisms?

Answer 466

Complex (undefined) media - inexpensively

Chemically defined media - fastidious organisms

Question 467

What is the main difference between selective, differential and enrichment media?

Answer 467

1. Selective media - allows growth of some microorganisms while preventing the growth of others based on some property. (McConkey agar selects between Gram-negative (grow) and Gram-positive cells (don’t grow).)
2. Differential media - some microorganisms appear differently due to some difference in their biology. (In MacConkey agar, acid-fermenting bacteria turn purple-pink while non-acid-fermenting bacteria turn yellowish-white.)
3. Enrichment media - provides nutrients that favor the growth of particular bacteria over others, designed to increase very small numbers of the desired type of organism to detectable levels. (Blood agar contains blood components and acts as an enrichment media for a number of potentially pathogenic bacteria.)

Question 468

Which type of media provides nutrients that favor the growth of particular bacteria over others?

Answer 468

Enrichment media

Question 469

What type of media makes some organisms appear differently due to some difference in their biology?

Answer 469

Differential media?

Question 470

What type of media allow the growth of some organisms while preventing the growth of others based on a property like Gram-negative or positive bacteria?

Answer 470

Selective media

Question 471

What type of media is MacConkey agar when it encourages growth of Gram-negative while preventing the growth of Gram-positive bacteria?

Answer 471

Selective media

Question 472

What type of media is MacConkey agar when acid-fermenting bacteria turn purple-pink and non-acid fermenting bacteria turn yellow-white?

Answer 472

Differential media

Question 473

What type of media is blood agar when it acts as an enrichment media for a number of potentially pathogenic species?

Answer 473

Enrichment media

Question 474

Match the definition with the type of media (selective, differential or enrichment):

• Allows growth of some microorganisms while preventing growth of others
• Some microorganisma appear differently due to some difference in their biology
• Provides nutrients that favoe the growth of particular bacteria over others

Answer 474

• Allows growth of some microorganisms while preventing growth of others - SELECTIVE
• Some microorganisma appear differently due to some difference in their biology - DIFFERENTIAL
• Provides nutrients that favoe the growth of particular bacteria over others - ENRICHMENT

Question 475

Which type of media allows growth of gram-negative bacteria over gram-positive?

Answer 475

Selective media

Question 476

What type of media makes acid-fermenting bacteria appear differently than non-acid-fermenting bacteria?

Answer 476

Differential media

Question 477

What type of media is blood agar?

Answer 477

Enrichment media

Question 478

What type of media is MacConkey agar?

Answer 478

Selective media - gram-negative grows, gram-positive does not

Differential media - acid-fermenting bacteria are purple-pink, non are yellow-white

Question 479

Describe how bacteria are grown in anaerobic conditions in liquid culture (FTM).

Answer 479

• Reducing media is used to grow bacterial cultures under anaerobic conditions in liquid cultures.
• Reducing media contain ingredients that chemically combine with dissolved oxygen and deplete oxygen in the culture medium by reducing O₂ to H₂O.
• Reducing media is stored in tightly capped test tubes to prevent the reducing agent in the media from being completely oxidized.
• FTM is a reducing agent.

Question 480

Reducing agents contain ingredients that do what?

Answer 480

Reduce O₂ to H₂O

Question 481

What are reducing agents like FTM used for?

Answer 481

Growing microorganisms in anaerobic conditions.

Question 482

What is FTM and does it do?

Answer 482

Fluid thioglycolate medium

Reduces O₂ to H₂O

Question 483

Describe how bacteria are grown in anaerobic conditions on Petri dishes.

Answer 483

• To grow microorganisms on petri dishes, chambers with an anaerobic atmosphere must be used.
• Small, temporary chambers can be used with packets that contain carbon dioxide and hydrogen. The hydrogen interacts with the free O₂ to make water in a reaction that requires a platinum catalyst.
• More frequent need for cultures in anaerobic conditions require glove boxes.
• Glove boxes are more permanent chambers filled with inert, oxygen-free gas.
• Rubber gloves allow the manipulation of objects inside the box and an airlock allows things to be passed into and out of the box without allowing in O₂.

Question 484

What two devices can be used to grow bacteria in anaerobic environment in petri dishes?

Answer 484

• Temporary chambers can be used with packets containing CO₂ and hydrogen where the hydrogen interacts with the O₂ to make water in the presence of a platinum catalyst.
• Glove boxes are more permanent and have gloves that allow maniupulation and an airlock to pass items in and out of the box

Question 485

Describe the plate method for isolating single colonies.

Answer 485

1. Sterilize loop
2. Dip inoculating loop in culture
3. Loop is streaked across one section of a plate
4. Sterilize loop
5. Loop is dragged through a small section of the first streak, which is then streaked over a second are of the plate
6. Sterilize loop
7. Loop is dragged through a small section of the second streak, which is then streaked over a third are of the plate.

The goal is to dilute the cells enough that single colonies are able to grow.

Question 486

When is the loop dipped in the culture when preparing a streak plate?

Answer 486

Only at the very beginning.

Question 487

Why are single colonies (like those from streak plates) important in microbiology?

Answer 487

Single (isolated) colonies are colonies that are founded by a single cell. In order to obtain a single colony, a single cell must be isolated on a plate so that it is far enough away from other cells that it can grow into a colony without touching growth from other cells.

Question 488

What is the goal of the streak plate method?

Answer 488

To obtain single colonies

Question 489

Describe the steps in binary fission.

Answer 489

1. Cell elongates and DNA is replicated
2. Cell wall and plasma membrane begin to constrict
3. Cross-wall forms, completely separating the two DNA copies
4. The cells separate

Question 490

What process do these steps represent?

1. Cell elongates
2. Cell wall and plasma membrane begin to constrict
3. Cross-wall forms, completely separating the two DNA copies
4. The cells separate

Answer 490

Binary fission

Question 491

Put these steps in the right order. What do they represent?

1. Cell wall and plasma membrane begin to constrict
2. Cell elongates and DNA is replicated
3. The cells separate
4. Cross-wall forms, completely separating the two DNA copies

Answer 491

1. Cell elongates and DNa is replicated
2. Cell wall and plasma membrane begin to constrict
3. Cross-wall forms, completely separating the two DNA copies
4. The cells separate

This is binary fission

Question 492

Draw a typical bacterial growth curve and label the four phases of growth.

A. Lag phase

B. Log phase

C. Stationary phase

D. Death phase

Answer 492

Question 493

In the bacterial growth phase, what is A?

Answer 493

Lag phase: Cells are not dividing but are metabolically active, preparing to divide (synthesizing cell components, replicating DNA, etc.)

Question 494

In the bacterial growth curve, what is represented by B?

Answer 494

Log phase: Cells are rapiding dividing and most metabolically active.

As this phase continues, nutrient availability in the media decreases while the concentrations of toxic molecules increases. Result is slowing of cell division and increase in cell death.

Question 495

What part of the bacterial growth curve is represented by C?

Answer 495

Stationary phase: Cell division slows and cell death increases to where they are roughly equal, so there is no net change in population of the culture.

Question 496

What does D represent in the bacterial growth curve?

Answer 496

Death phase: The rate of cell death exceeds the new cells being produced through cell division, so the population of the culture decreases.

Question 497

Put the phases (below) from the bacterial growth curve in order.

Stationary phase

Log phase

Death phase

Lag phase

Answer 497

A. Lag phase

B. Log phase

C. Stationary phase

D. Death phase

Question 498

In what phase of the bacterial growth curve does death of cells exceed growth?

Answer 498

Death phase (D)

Question 499

In what phase of the bacterial growth curve are cells metabolically active but not yet dividing?

Answer 499

Lag phase (A)

Question 500

In what phase of the bacterial growth chart does cell division slow and cell death increasesto where they are roughly equal?

Answer 500

Stationary phase (C)

Question 501

In what phase of bacterial growth curve are cells rapidly dividing and are most metabolically active?

Answer 501

Log phase (B)

Question 502

As what phase of the bacterial growth curve continues, are nutrients decreasing while toxic molecule concentrations increase, the result being a slowing of growth?

Answer 502

Log phase (B)

Question 503

Briefly describe plate counts and advantages and disadvantages to measuring bacterial growth.

Answer 503

Plate count: The idea behind a plate count is to spread a volume of liquid on a plate, allowing individual cells on the plate (which cannot be seen with th enaked eye) to grow into colonies (which can be seen with the naked eye) and count the colonies.

The results from a plate count are CFUs (colony forming units) since some bacteria form chains which are difficult to separate. Because of the difficulty of CFUs growing together, serial dilutions are necessary to get a countable result.

Advantages: inexpensive materials and only counting living cells (the only ones to grow in a culture).

Disadvantages: takes time (usually ~ 24 hours) to get readable results.

Question 504

Describe the principle of turbidity used to measure bacterial growth.

Answer 504

Based on the principle that cells scatter light passing through the culture and that the higher the concentration, the less light is able to pass through the culture. A spectrophotometer is used to measure absorbance (optical density (OD)) of a culture.

Advantages: Get results rapidly.

Disadvantages: Requires expensive equipment (spectrophotometer). Also, to get actual concentration, must first make a standard curve by measuring OD as well as measuring the concentration using another technique (plate count or microsopic count).

Question 505

Describe the method of direct microscopic count in measuring bacterial growth.

Answer 505

Direct microscopic count: 0.01 mL of culture is spread on a Petroff-Hausser cell counter (a slide that has a counting grid). Counting the number of cells results in a measurement of concentration (cells per volume).

Advantages: get results relatively quickly

Disadvantages: expensive equipment (counter & microscope) and get non-living cells in the count

Question 506

What are the advantages and disadvantages of the plate count method for measuring bacterial growth?

Answer 506

Plate count

Advantages: inexpensive, get live cell count (cells that will grown into colonies)

Disadvantages: Time-consuming (wait 24 hours)

Question 507

What are the advantages and disadvantages of the direct microscopic count method for measuring bacterial growth?

Answer 507

Direct microscope count

Advantages: get results rapidly

Disadvantages: expensive equipment, can’t differentiate non-living cells

Question 508

What are the advantages and disadvantages of the turbidity method for measuring bacterial growth?

Answer 508

Turbidity

Advantages: Get results quickly

Disadvantages: expensive equipment and also need another measurement of the concentration like plate count or direct microscopic count. Lastly, measurement of different cell types are not comparable, as differences in cell size between species may cause cells to scatter more or less light. Only measures absorbance.

Question 509

How do you do a plate count to measure bacterial growth?

Answer 509

Spread a volume of liquid on a plate, allow individual cells on the plate to grow into colonies and count the colonies (result is in CFUs). Serial dilutions might be necessary to get a countable result.

Question 510

With what bacterial growth count method is serial dilution often used to get a countable result?

Answer 510

Plate count

Question 511

How do you perform a direct microscopic count of bacterial growth?

Answer 511

Put 0.01 mL of a culture is spread on a Petroff-Hausser cell counter. Each grid represents a known volume. Counting the cells in that box results in a measurement of concentration (cells per volume).

Question 512

What is the cell counter called that is used to perform a direct microscopic count of bacterial growth?

Answer 512

Petroff-Hausser

Question 513

How do you perform the turbidity method of bacterial growth?

Answer 513

Put culture in a tube and pass through a spectrophotometer to measure the optical density.

Question 514

What does the turbidity of a culture measure?

Answer 514

Optical density

Question 515

What instrument is used to measure turbidity of a culture?

Answer 515

Spectrophotometer