Microbial Metabolism Flashcards
1
Q
What is metabolism?
A
The SUM total of chemical reactions that take place within cells (of an organism)
2
Q
What does every cell acquire/need?
A
Nutrients
3
Q
Metabolism requires energy from ? (2)
A
-light
-catabolism of nutrients
4
Q
Energy is stored in ?
A
ATP
5
Q
Cells catabolize nutrients to form?
A
Precursor metabolites
6
Q
*how to remember precursor metabolites
A
-eat food
-food breaks down (catabolism)
-molecules from food can be used as energy (ATP) or synthesize/build other structures (amino acids, nucleotides)
This is the precursor metabolites
-They then are used to anabolically for cell growth by assembling macromolecules.
7
Q
Cells reproduced once they ___________ in size.
A
Doubled
8
Q
What type of chemical reactions underly metabolism? (4)
A
-catabolism (breakdown)
-anabolis (synthesis)
-oxidation (loss of electron to—> reduced agent)
-reduction(gained electron from oxidizing agent)
9
Q
Does Catabolic pathways consume or release energy
A
-RELEASE energy
10
Q
What type of reactions are catabolic pathways?
A
Exergonic
11
Q
In catabolic pathways, where is the energy stored ?
When does it use that energy?
A
-Organic molecules
-until it needs to do work in the cell
12
Q
Does anabolic pathways consume or release energy?
A
-consume energy
13
Q
What happens in catabolic pathways.
A
breakdown complex molecules to simpler compounds
14
Q
What happens in anabolic pathways?
A
Consume energy to build complicated molecule from simpler molecules.
15
Q
What type of reaction is anabolic pathway?
A
Endergonic reaction
16
Q
Free energy is released by reactions and is made available to perform ?
A
Work
17
Q
Reactions in closed systems eventually reach equilibrium and can?
A
Do no work
18
Q
A cell that has reached metabolic equilibrium is?
A
Dead
19
Q
What is a defining feature of life?***
A
Disequilibrium
20
Q
Why do cells maintain disequilibrium?
A
Because they are open with a constant flow of material in and out of the cell.
*a cell continuous to do work throughout its life
21
Q
What happens to the energy in an explosion?
A
A lot of the energy is LOST
22
Q
The product of one reaction does not accumulate,
What happens to it?
A
It becomes the reactant in the next step
23
Q
What is the term for a huge amount of energy released all at once?
A
Explosion
24
Q
Sunlight provides a daily source of what ?
And to what type of organism?
A
-Free energy
-photosynthetic organism
25
Nonphotosynthetic organisms depend on a transfer of free energy from? In the form of what ?
-Photosynthetic organisms
-nutrients/food
26
Oxidation and reductions always occur?
Simultaneously
27
Cells use _______________________ to carry electrons
(Oxidation and reduction)
-electron carrier molecules
28
What are three important electron carriers?
(Oxidation and reduction)
1. Nicotinamide adenine dinucleotide (NAD+)—->NADH
2. Nicothnamide adenine dinucleotide phosphate (NADP+)—->NADPH
3. Flavine adenine dinucleotide (FAD)—-> FADH2
29
Energy released from nutrients can be stored in high energy phosphate bonds of?
ATP
30
What is phosphorylation?
-inorganic phosphate is added to substrate.
31
Cells phosphorylation ADP to ATP in three ways.
What are they?
-substrate-level phosphorylation
-oxidative phosphorylation
-photophosphorylation
32
Anabolic pathways use some energy of ATP by breaking a?
Phosphate bond (that releases energy)
33
What is the role of an enzyme in metabolism?
It is a catalyst (assist in reaction)
34
Enzymes are what type of catalyst?
Organic
35
Enzymes are permanently changed in a reaction?
T/F
FALSE
36
Do enzymes reduce or raise activation energies ?
Reduce
37
Enzymes are ________ for a substrate.
Specific
38
What are the six categories of enzymes based on mode of action?
-hydrolases
-isomerases
-ligases or polymerases
-lyases
-oxidoreductases
-transferases
39
Role of hydrolases?
Remove hydrogens
40
Role of isomerases?
Rearrange atoms
41
Role of ligases or polymerases?
Join molecules (add monomers)
42
Role of lyases?
Breaking of chemical bonds
43
Role of Transferases?
-transfer functional groups.
44
Turnerover number is generally ____________ molecules per second. (Enzymes)
1-10,000
45
Most enzymes are ?
Proteins (main portion)
46
What is a holoenzyme?
Enzyme that is composed of :
-apoenzymes (protein portion)
-cofactors (nonprotein portion)
47
Apoenzymes are_____________ until it is bound to cofactors
Inactive
48
Examples of cofactors
-inorganic ions [copper, iron]
-coenzymes
49
Factors that influence the rate of enzymatic reactions?
(4)
-temperature
-P.H.
-enzyme and substrate concentrations
-presence of inhibitors
50
Explain how temperature affects enzymatic reactions ?
-too cold?
-warm?
-too hot?
-too cold - slowed down.
-warm- is at its best.
-too hot- protein becomes denatured.
51
What happens to a protein when the temperature is too high?
-It becomes denatured.
52
What can cause enzymes to be denatured?
-temperature
-PH
53
Optimum PH?
7
54
With lots of substrate concentration does the enzyme activity work slow or fast?
Fast
55
What are inhibitors?
Substances that block an enzyme’s active site.
56
Do inhibitors denature enzymes?
Y/N
NO
57
What are the types of inhibitors?
-Competitive inhibitors
-Noncompetitive inhibitors (aka Allosteric inhibitor)
58
Some antibiotics use which type of inhibitor?
-competitive
59
What molecules and elements are necessary for life?
-nucleic acids
-proteins
-lipids
-carbohydrates
60
Organisms oxidize ____________ as the primary energy source for _____________ reactions.
-carbohydrates
-anabolic
61
Glucose catabolism is called?
-glycolysis
62
Cellular respiration utilizes what processes?
-glycolysis
-Krebs cycle
-electron transport chain
63
Fermentation uses what processes ?
-glycolysis then converts pyruvic acid into other compounds .
64
The oxidation of glucose to pyruvic acid, produces what ?
-ATP
-NADH
65
How many pyruvic acid is made from glycolysis?
2
66
Where does glycolysis occur?
-cytoplasm of most cells
67
How many stages of glycolysis ?
How many steps?
-3 stages
-10 steps
68
What are the 3 stages in glycolysis?
-energy-investment stage
-lysis stage
-energy-conserving stage
69
What are the products of glycolysis?
2 pyruvic acid, 4 ATP, 2 NADH, 2H+
70
What is the net total products of glycolysis.
2 pyruvic acid, 2 ATP, 2 NADH, 2H+
71
What two pathways are used as an alternative to glycolysis?
-Pentose phosphate pathway
-Entner-Doudoroff pathway
72
Do the alternative pathways yield more or fewer molecules of ATP?
FEWER
73
What type of pathway is mostly seen in photosynthesizing organisms?
-Pentose Phosphate pathway
74
Pentose phosphate pathways
(Things to know)
-uses Pentoses and NADPH
-produce 1ATP + 2 NADPH
-operate WITH glycolysis
-used to make precursor metabolites for nucleotides and amino acids
75
Entner-Doudoroff pathway
(Things to know)
-Produces 2 NADPH + 1ATP
-used INSTEAD of glycolysis
-Pseudomonas, Rhizobium, Agrobacterium, Enterococcus faecalis
76
Pyruvic acid is completely oxidized to produce ATP by a series of _________ _________.
-Redox reactions
77
What is a redox reaction ?
Oxidation reduction reaction
78
What are the stages of cellular respiration ?
-Synthesis of acetyl-CoA (intermediate step)
-Krebs cycle
-Electron Transport Chain (ETC)
79
How many Acetyl-CoA are made after glycolysis and why that number?
-2 molecules of Acetyl-CoA are synthesized
- 1 for each pyruvic acids from glycolysis (2)
80
Products of the intermediate step?
(Synthesis of Acetyl-CoA)
-2 Acetyl-CoA
-2 NADH
-2 CO2
81
In the Krebs cycle a large amount of energy remains in the bonds of ?
-Acetyl-CoA enzyme A
82
The Krebs cycle transfers much of this energy to coenzymes ________ and ________?
-NAD+
-FAD
83
Where does the Krebs cycle occur in prokaryotes?
-cytoplasm/cytosol
(Prokaryotes have no organelles)[bacteria]
84
Where does the Krebs cycle occur in eukaryotes?
-matrix of the MITOCHONDRIA
(Animal cells have organelles)
85
How many times does the Krebs cycle happen ?
Why that number?
-Happens 2 times
-1 for each molecule of acetyl-coa
86
Is the intermediate step an oxidation or reduction redaction?
What is it oxidizing/reducing?
-Reduction
-pyruvic acid
87
Is the Krebs cycle an oxidation or reduction reaction ?
What is it oxidizing/reducing?
-Oxidation
-acetyl-coa
88
What are the products of the Krebs cycle?
3- NADH
1-FADH2
1-ATP
89
What is another name for the Krebs cycle?
-Citric Acid cycle
90
Is the electron transport chain an oxidizing or reducing reaction?
Both oxidizing and reducing as electrons are passed down the chain.
91
What are 4 major classes of electron carriers in the electron transport chain ?
-flavoproteins
-ubiquinones
-metal-containing proteins
-cytochromes
92
Energy released can be used to produce ATP by ?
Chemiosmosis
93
What is the final electron acceptor in the electron transport chain ?
Oxygen
94
Chemiosmosis
(Things to know)
-use of electrochemical gradients to generate ATP
-creates a proton gradient from energy released in redox reactions of ETC
-protons flow down the electrochemical gradient through ATP synthases that phosphorylate ADP to ATP
-called OXIDATIVE phosphorylation because proton gradient created by oxidation of components of ETC
- about 34 ATP molecules formed from one molecule of glucose
95
Where does glycolysis happen in eukaryotes?
Cytoplasm
96
Where does glycolysis happen in prokaryotes?
Cytoplasm
(“PROkaryotes”….”PLASM”)
97
Where does the intermediate step happen in eukaryotes?
Mitochondrial matrix
98
Where does the intermediate step happen in prokaryotes?
Cytoplasm
(“PROkaryotes”….”PLASM”)
99
Where does the Krebs cycle happen in eukaryotes?
Mitochondrial matrix
100
Where does the Krebs cycle happen in prokaryotes?
Cytoplasm
(“PROkaryotes”….”PLASM”)
101
Where does the electron transport chain occur in eukaryotes?
Mitochondrial inner membrane
(Remember ETC happens in “membranes”)
102
Where does the electron transport chain occur in prokaryotes?
Plasma membrane
(Remember ETC happens in “membranes”)
(“PROkaryotes”….”PLASM”)
103
Easy way to remember where aerobic respiration (glycolysis, intermediate step, Krebs cycle, Electron Transport Chain[ETC]) happens ***
-Prokaryotes (bacteria) have no internal organelles so the process happens inside its cytoplasm and ETC happens in plasma membrane -THINK “plasm” “prokaryotes” ETC just happens in membrane
-eukaryotes (animals) have organelles inside cell, so besides glycolysis which occurs in cytoplasm , occurs in mitochondria but again for ETC happens in membrane just mitochondria membrane
104
Respiration formula?
C6 H12 O6 + 6O2———> 6CO2 + 6H2O + 38ATP +HEAT
105
In respiration, where is C6 H12 O6 found?
(Glucose)
Glycolysis
106
In respiration, where is 6O2 found?
(Oxygen)
Electric transport chain
107
In respiration where is 6CO2 found?
-Intermediate cycle
-Krebs cycle
108
In respiration, where is 6H2O found?
End of electron transport chain
109
In respiration where is 38ATP found
-glycolysis
-Krebs cycle
-electric transport chain
110
Aerobic respirations final electron acceptor is ?
Oxygen
111
Anaerobic respiration’s final electron acceptor is ?
NOT O2
(Yields less energy)
112
Electron acceptors in anaerobic respiration ?
-NO3
-SO4
CO3^2
113
What is the main molecule fermented is fermentation ?
Carbohydrate
114
Is fermentation a aerobic or anaerobic process?
Anaerobic
115
Fermentation does not use what steps for ATP
Does not use:
-krebs cycle
-electron transport chain
116
What is the final electron acceptor in fermentation ?
-organic molecule
117
Fermentation has an intermediate step.
T/F
False
118
Fermentation depends on glycolysis product.
T/F
TRUE
It requires pyruvic acid from glycolysis
119
Fermentation process*
-glucose molecule used in glycolysis
-pyruvic acid from end product glycolysis used to ferment.
-uses organism to ferment and create different products depending on organism.
120
Examples of organisms used for fermentation
TESTABLE?
-propionibacterium
-aspergillus, lactobacillus, streptococcus
-saccharomyces
-clostridium
121
Fermentation products.
-CO2 propionic acid (Swiss cheese)
-lactic acid (cheddar chees, yogurt, soy sauce)
-CO2 ethanol (wine, beer)
-acetone, isopropanol (nail polish remover, rubbing alcohol)
122
Alcohol fermentation produces?
Ethyl alcohol + CO2
123
Lactic acid fermentation produces?
Lactic acid
124
Homolactic fermentation produces?
Lactic acid only
125
Heterolactic fermentation produces?
Lactic acid & other compounds
126
When testing for carbohydrate fermentation
What color indicates positive carbohydrate fermentation ?
What color indicates negative carbohydrate fermentation.
-phenyl red indicator turns YELLOW when positive
-phenyl red indicator stays RED when negative
-RED -
-YELLOW +
127
When testing for carbohydrate fermentation what does a clear color mean/represent ?
Clear means organism did not grow= non result
128
In lipid catabolism what is lipid split into ?
-glycerol
-fatty acids
129
An enzyme that breaks down lipids is called ?
Lipase
130
An enzyme that breaks down a protein is called?
Protease
131
Steps for protein catabolism
-protein gets broken down by protease into Amino acids
-deamination
-decarboxylation
-dehydrogenation
- turns into organic acid
-used for Krebs cycle
132
How do you identify a bacteria ?
Biochemical testing?
(Think tree diagram)
133
What is the opposite of respiration ?
Photosynthesis
134
Describe photo in photosynthesis
Conversion of light energy into chemical energy (ATP)
-light dependent reactions
135
Describe synthesis in photosynthesis
Fixing carbon into organic molecule
-light-independent (dark) reaction
-calvin benson cycle
136
Oxygenic formula
(Photosynthesis)
6 CO2 + 12 H2O + Light energy ——-> C6H12O6 + 6 O2 + 6 H2O
137
Anoxygenic formula
(Photosynthesis)
CO2 + 2 H2S + light energy ——-> [CH2O] + 2 A + H2O
138
Steps in cyclic photophosphorylation
-light (source of energy) goes into chlorophyll
-excited electrons use Electron transport chain
-ATP is made from this
-electron carrier goes back to chlorophyll
-repeat process?
139
Noncyclic photophosphorylation is like what ?
Aerobic respiration in the Electron transport chain
140
Does the Calvin-benson cycle need solar energy ?
Does not need but uses energy from sunlight
141
What is a photoautotroph?
Makes its own food
142
Halobacterium uses bacteriorhodopsin or chlorophyll to generate electrons for a chemiosmotic proton pump ?
Bacterirohodopsin
143
All organisms require an energy source.
What can it be?
-chemical energy source
-light energy source
144
What are amphibolic pathways?
Metabolic pathways that have both catabolic and anabolic functions.
*go back & forth as needed.
145
ATP produced by catabolism is used to drive ?
Anabolism
146
Catabolic pathways produce precursor metabolites to use ?
For Construction of macromolecule
147
If two energy sources are available , cells catabolize which first?
The more energy efficient first
