Biology Chapters 8/9

Question 0

What did Jan van Helmont conclude from his experiments?

Answer 0

Mass gained in plants is mostly due to water.

Question 1

What occurs in the process of photosynthesis?

Answer 1

Plants use energy from sunlight to convert water and carbon dioxide into high-energy carbohydrates and oxygen.

Question 2

What substance was produced by the mint plant in Joseph Priestley’s experiment?

Answer 2

Oxygen.

Question 3

What did Jan Ingenhousz show?

Answer 3

Plants only release oxygen when they are exposed to light.

Question 4

What is the chemical equation for photosynthesis?

Answer 4

6CO2 + 6H20 –> C6H12O6 + 6O2

Question 5

What does photosynthesis require?

Answer 5

Water, carbon dioxide, light, and chlorophyll.

Question 6

What are light-absorbing molecules that gather the sun’s energy? What is the principal one in plants?

Answer 6

Pigments, chlorophyll

Question 7

What is a thylakoid?

Answer 7

A saclike photosynthetic membrane found in chloroplasts.

Question 8

What is a granum?

Answer 8

A stack of thylakoids.

Question 9

What is the region outside the thylakoid membrane called?

Answer 9

The stroma.

Question 10

What are photosystems?

Answer 10

Clusters of chlorophyll and other pigments made by proteins in the thylakoid membrane.

Question 11

What are the two stages of photosynthesis called?

Answer 11

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

Question 12

What is the reactant of light-dependent reactions? the product?

Answer 12

Water

Oxygen

Question 13

What is the reactant of the Calvin cycle? the product?

Answer 13

Carbon dioxide

Glucose

Question 14

True or false: Electrons gain energy when they are excited by light in the chlorophyll.

Answer 14

True.

Question 15

What is a carrier molecule?

Answer 15

A compound that can accept a pair of high-energy electrons and transfer them along with most of their energy to another molecule.

Question 16

What is the carrier molecule involved in photosynthesis?

Answer 16

NADP+

Question 17

How does NADP+ become NADPH?

Answer 17

NADP accepts and hold 2 high-energy electrons and a hydrogen ion.

Question 18

True or false: Light dependent reactions convert ATP into ADP.

Answer 18

False (they convert ADP into ATP)

Question 19

When is NADP+ converted into NADPH?

Answer 19

During the light-dependent reactions.

Question 20

Where do the light-dependent reactions take place?

Answer 20

Thylakoids

Question 21

True or false: High-energy electrons move through the electron transport chain from photosystem I to photosystem II.

Answer 21

False (they move from photosystem II to photosystem I)

Question 22

What process produces ATP?

Answer 22

ATP synthase.

Question 23

What does the Calvin cycle use to produce sugars?

Answer 23

The energy from ATP and NADPH.

Question 24

Where do carbon dioxide molecules that enter the Calvin cycle come from?

Answer 24

The atmosphere.

Question 25

True or false: The Calvin cycle uses six molecules of carbon dioxide to produce a single 6-carbon sugar molecule.

Answer 25

True

Question 26

What three factors affect the rate of photosynthesis?

Answer 26

Water, temperature, and light.

Question 27

What is a calorie?

Answer 27

The amount of energy it takes to raise the temperature of 1 gram of water 1 degree celsius.

Question 28

How many calories make up 1 Calorie?

Answer 28

1,000.

Question 29

What is the first stage of cellular respiration called?

Answer 29

Glycolysis

Question 30

What is cellular respiration?

Answer 30

The process that releases energy by breaking down glucose and other food molecules in the presence of oxygen.

Question 31

What is the chemical equation for cellular respiration?

Answer 31

6O2 + C6H12O6 ---> 6CO2 + 6H2O + Energy

Question 32

What are the second and third stages of cellular respiration?

Answer 32

The Krebs cycle and the electron transport chain.

Question 33

What would happen if cellular respiration was only one stage?

Answer 33

All the energy from glucose would be released at once.

Question 34

Where does glycolysis take place?

Answer 34

In the cytosol.

Question 35

Where do the Krebs cycle and electron transport chain take place?

Answer 35

In the mitochindria

Question 36

What is glycolysis?

Answer 36

The process in which one molecule of glucose is broken in half, producing two molecules of pyruvic acid, a 3-carbon compound.

Question 37

What fuels glycolysis?

Answer 37

Two molecules of ATP.

Question 38

What is the net gain of ATP after glycolysis?

Answer 38

2 ATP

Question 39

What is NAD+?

Answer 39

An electron carrier that hold 4 high-energy electrons.

Question 40

What is the function of NAD+ in glycolysis?

Answer 40

Holding electrons until they are needed in other molecules, helping pass glucose to other cell parts.

Question 41

What does NAD+ become after glycolysis?

Answer 41

NADH

Question 42

What process is used to produce energy in cells without oxygen?

Answer 42

Fermentation.

Question 43

What is fermentation?

Answer 43

An anaerobic process that releases energy from food molecules by producing ATP.

Question 44

How does fermentation allow glycolysis to continue?

Answer 44

It turns NADH back into NAD+.

Question 45

What are the two main types of fermentation?

Answer 45

Alcoholic and lactic acid.

Question 46

What organisms use alcoholic fermentation?

Answer 46

Yeasts and other microorganisms

Question 47

What is the equation for alcoholic fermentation?

Answer 47

Pyruvic acid + NADH --> alcohol + carbon dioxide + NAD+

Question 48

What happens to alcohol produced from alcoholic fermentation when bread is baked?

Answer 48

The alcohol evaporates.

Question 49

What is the equation for lactic acid fermentation?

Answer 49

Pyruvic acid + NADH ---> lactic acid + NAD+

Question 50

When is lactic acid fermentation most commonly used by human beings?

Answer 50

During rapid exercise.

Question 51

How much chemical energy from glucose is used during glycolysis?

Answer 51

10%

Question 52

True or false: The Krebs cycle and the electron transport chain are aerobic.

Answer 52

True

Question 53

What happens to pyruvic acid during the Krebs cycle?

Answer 53

It is broken down into carbon dioxide in a series of energy-extracting reactions.

Question 54

Why is the Krebs cycle often referred to as the citric acid cycle?

Answer 54

Citric acid is the first compound formed during the reactions of the Krebs cycle.

Question 55

When does the Krebs cycle begin?

Answer 55

When pyruvic acid produced during glycolsis enters the mitochondrion.

Question 56

What happens to the 3 carbon atoms in pyuvic acid when it is broken down?

Answer 56

1 becomes part of a carbon dioxide molecule while the other 2 join a compound called coenzyme A to form acetlyl-CoA.

Question 57

What happens to the carbon dioxide molecule produced when pyruvic acid is broken down?

Answer 57

It is released into the air.

Question 58

How is citric acid produced?

Answer 58

Acetyl-CoA adda a 2-carbon acetyl group to a 4-carbon molecule, producing a citric acid molecule.

Question 59

How many carbon dioxide molecules during the energy extraction part of the Krebs cycle?

Answer 59

2

Question 60

What is the "energy tally" from 1 molecule of pyruvic acid during the Krebs cycle?

Answer 60

4 NADH, 1 FADH2, and 1 ATP.

Question 61

Why is the 4-carbon compound generated in the breakdown of citric acid the only permanent compound in the Krebs cycle?

Answer 61

It accepts another 2-carbon acetyl group, starting the process over again.

Question 62

How many total ATP molecules are produced during cellular respiration?

Answer 62

36

Question 63

Why does oxygen allow more ATP molecules to produce?

Answer 63

The Krebs cycle and electron transport chain are aerobic.

Question 64

What happens to the leftover energy of glucose after all the ATP molecules are produced?

Answer 64

It is released as heat.

Question 65

What are three sources of ATP runners use before a race?

Answer 65

Their muscles, lactic acid fermentation, and cellular respiration.

Question 66

What is the only molecule that can be used to get rid of lactic acid?

Answer 66

Oxygen.

Question 67

True or false: Runners use lactic acid fermentation to supply energy for short races while they used cellular respiration for long races.

Answer 67

True