Question 1

Which of the following best describes the primary function of the light-dependent reactions of photosynthesis?

Accepted Answer

To generate ATP and NADPH by converting solar energy into chemical energy

Question 2

Where in the chloroplast do the light-dependent reactions occur?

Accepted Answer

In the thylakoid membranes

Question 3

Which of the following equations correctly summarizes the light-dependent reactions of photosynthesis?

Accepted Answer

$$H_2O + NADP^+ + ADP \rightarrow O_2$ + NADPH + ATP$$

Question 4

A plant is exposed to a chemical that blocks the splitting of water during photosynthesis. Which of the following would be the most immediate effect?

Accepted Answer

O$$_2$$ production would cease

Question 5

Which component of the photosystem is directly responsible for capturing photons of light?

Accepted Answer

Light-harvesting complex

Question 6

During the Calvin-Benson cycle, which molecule is regenerated to allow the cycle to continue?

Accepted Answer

Ribulose bisphosphate (RuBP)

Question 7

Which of the following best explains why plants need both Photosystem I and Photosystem II?

Accepted Answer

The two photosystems work together to efficiently transfer electrons from water to NADP$$^+$$, generating both ATP and NADPH

Question 8

A mutation prevents the formation of grana in a plant's chloroplasts. Which process would be most directly affected?

Accepted Answer

Light-dependent reactions

Question 9

Which of the following is a correct summary equation for the Calvin-Benson cycle (for the production of one glucose molecule)?

Accepted Answer

$$6CO_2 + 18ATP + 12NADPH \rightarrow C_6H_{12}O_6$ + 18ADP + 12NADP^+$$

Question 10

Which of the following statements about chemiosmosis in chloroplasts is correct?

Accepted Answer

It involves the movement of protons from the stroma into the thylakoid space, generating a proton gradient used to synthesize ATP

Question 11

If a plant is placed in an environment with no light, which of the following processes would be most immediately affected?

Accepted Answer

The light-dependent reactions

Question 12

Which pigment is primarily responsible for the absorption of light energy during photosynthesis?

Accepted Answer

Chlorophyll

Question 13

What is the main role of accessory pigments such as carotenoids in photosynthesis?

Accepted Answer

To absorb additional wavelengths of light and transfer the energy to chlorophyll

Question 14

Which of the following best describes the fate of electrons lost from Photosystem II during the light-dependent reactions?

Accepted Answer

They are replaced by electrons from the splitting of water

Question 15

A scientist measures the rate of oxygen production in a plant under different wavelengths of light. Which process is being directly measured?

Accepted Answer

The light-dependent reactions

Question 16

Which of the following is NOT a product of the light-dependent reactions?

Accepted Answer

Glucose

Question 17

During which phase of the Calvin-Benson cycle is ATP consumed?

Accepted Answer

Carbon fixation and regeneration of ribulose bisphosphate

Question 18

If a plant's thylakoid membranes were damaged, which of the following would be most directly affected?

Accepted Answer

ATP and NADPH production

Question 19

Which of the following best explains why the Calvin-Benson cycle is considered 'light-independent'?

Accepted Answer

It can occur in the dark as long as ATP and NADPH are available

Question 20

A plant is genetically engineered to lack NADP$$^+. $$Which of the following would be the most immediate consequence?

Accepted Answer

The plant would be unable to produce NADPH, halting the Calvin-Benson cycle

Photosynthesis: Capturing Solar Energy in Plants

Study Guide - Practice Questions