photosynthesis quiz questions

Question 1

The process whereby plants capture energy and make complex molecules is known as

Answer 1

photosynthesis

Question 2

suspended in the fluid stroma of chloroplasts are …

Answer 2

stacks of thylakoids called grana.

Question 3

The sun is considered the ultimate source of energy for life on Earth because

Answer 3

either photosynthetic organisms or organisms that have eaten them provide energy for all other organisms on Earth.

Question 4

The energy from the sun is converted into chemical energy in the form of organic compounds in a series of linked chemical reactions called a

Answer 4

Biochemical Pathway

Question 5

The role of chlorophyll in photosynthesis is to

Answer 5

Absorb light energy

Question 6

What happens when a chlorophyll molecule absorbs light ?

Answer 6

Some of its electrons are raised to a higher energy level

Question 7

When electrons of a chlorophyll molecule are raised to a higher energy level,

Answer 7

They enter an electron transport chain

Question 8

NADP+ is important in photosynthesis because it

Answer 8

Provides protons and electrons for some reactions

Question 9

The electrons of photosystem I

Answer 9

are eventually replaced by electrons from photosystem II.

Question 10

The source of oxygen produced during photosynthesis is

Answer 10

water

Question 11

The major atmospheric byproduct of photosynthesis is

Answer 11

oxygen

Question 12

During the Calvin cycle, carbon-containing molecules are produced from

Answer 12

carbon atoms from carbon dioxide in the air and hydrogen atoms from NADPH.

Question 13

Which of the following processes occurs in the thylakoid membrane and converts captured light energy into chemical energy?

Answer 13

chemiosmosis

Question 14

Chemiosmosis in the thylakoid membrane is directly responsible for

Answer 14

providing the energy to produce ATP molecules.

Question 15

Products of the light reactions of photosynthesis that provide energy for the Calvin cycle are

Answer 15

ATP and NADPH

Question 16

The Calvin cycle of photosynthesis

Answer 16

All of the above

Question 17

The energy used in the Calvin cycle for the production of carbohydrate molecules comes from

Answer 17

ATP made in the light reactions of photosynthesis.

Question 18

During photosynthesis, the series of reactions that create the complex carbohydrates needed for energy and growth is called

Answer 18

the Calvin Cycle

Question 19

All organic molecules contain carbon atoms that ultimately can be traced back in the food chain to

Answer 19

carbon dioxide from the atmosphere.

Question 20

Which of the following can be produced from the products of the Calvin cycle?

Answer 20

Lipids , carbohydrates , proteins

Question 21

Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin cycle?

Answer 21

ATP and NADPH

Question 22

All of the events listed below occur in the light reactions of photosynthesis except

Answer 22

carbon dioxide is incorporated into PGA.

Question 23

In mitochondria, chemiosmosis translocates protons from the matrix into the intermembrane space, whereas in chloroplasts, chemiosmosis translocates protons from

Answer 23

the stroma to the thylakoid space.

Question 24

How many turns of the Calvin cycle will it take to make one molecule of glucose ?

Answer 24

6

Question 25

How are the light reactions and the Calvin cycle (dark reactions) of photosynthesis dependent on each other?

Answer 25

The 18 ATP molecules and the 12 NADPH molecules produced during the light reactions are needed to power the Calvin cycle, and the 18 ADP molecules and 12 NADP+ molecules from the Calvin cycle are returned to the light reactions.

Question 26

Which of the following statements best represents the relationships between the light reactions and the Calvin cycle?

Answer 26

The light reactions provide ATP and NADPH to the Calvin cycle, and the cycle returns ADP, mc050-1.jpgi, and NADP+ to the light reactions.

Question 27

Photorespiration occurs when rubisco reacts RuBP with

Answer 27

O2

Question 28

Inside an active mitochondrion, most electrons follow which pathway?

Answer 28

citric acid cycle ® NADH ® electron transport chain ® oxygen

Question 29

Which of the following normally occurs regardless of whether or not oxygen (O2) is present?

Answer 29

glycolysis

Question 30

In chemiosmosis, what is the most direct source of energy that is used to convert ADP + to ATP?

Answer 30

energy released from movement of protons through ATP synthase, down their electrochemical gradient

Question 31

The immediate energy source that drives ATP synthesis by ATP synthase during oxidative phosphorylation is the

Answer 31

H+ movement down its concentration gradient.

Question 32

What does the chemiosmotic process in chloroplasts involve?

Answer 32

establishment of a proton gradient across the thylakoid membrane

Question 33

When oxygen is released as a result of photosynthesis, it is a direct by-product of

Answer 33

splitting water molecules

Question 34

Why is energy required to move the hydrogen ions across the membrane in the direction indicated in Figure 1-1?

Answer 34

Energy is needed as the hydrogen ions are being pumped against the concentration gradient.

Question 35

What is proton-motive force?

Answer 35

the force provided by a transmembrane hydrogen ion gradient

Question 36

Which of the following sequences correctly represents the flow of electrons during photosynthesis?

Answer 36

H2O ® NADPH ® Calvin cycle

Question 37

The pH of the inner thylakoid space has been measured, as have the pH of the stroma and of the cytosol of a particular plant cell. Which, if any, relationship would you expect to find?

Answer 37

The pH within the thylakoid is less than that of the stroma.

Question 38

What is the primary function of the Calvin cycle?

Answer 38

synthesize simple sugars from carbon dioxide

Question 39

Which of the following normally occurs regardless of whether or not oxygen (O2) is present?

Answer 39

Glycolysis