Question 1

Which of the following best explains why chlorophyll appears green to the human eye?

Accepted Answer

Chlorophyll reflects green wavelengths and absorbs red and blue.

Question 2

Which equation correctly represents the relationship between the energy ($$E) of a $$photon and its wavelength ($$\lambda$$)?

Accepted Answer

$$E = \dfrac{hc}{\lambda}$$

Question 3

What is the primary function of the light reactions in photosynthesis?

Accepted Answer

To generate ATP and NADPH for the Calvin cycle.

Question 4

Which of the following is a product of Photosystem II during the light reactions?

Accepted Answer

Oxygen ($$O_2)$$

Question 5

Where in the chloroplast does the Calvin cycle take place?

Accepted Answer

Stroma

Question 6

Which molecule is both phosphorylated and reduced during the Calvin cycle?

Accepted Answer

3-phosphoglycerate (3-PGA)

Question 7

Why is photorespiration considered inefficient for C3 plants?

Accepted Answer

It consumes oxygen and releases carbon dioxide without producing ATP or sugars.

Question 8

Which of the following best describes the role of Rubisco in the Calvin cycle?

Accepted Answer

It catalyzes the fixation of carbon dioxide to RuBP.

Question 9

How do C4 plants minimize photorespiration?

Accepted Answer

By spatially separating carbon fixation and the Calvin cycle.

Question 10

Which of the following statements about the proton gradient in photosynthesis is correct?

Accepted Answer

It drives ATP synthesis as protons flow from the thylakoid lumen to the stroma.

Question 11

Which of the following is a correct comparison between photosynthesis and cellular respiration?

Accepted Answer

Photosynthesis stores energy in glucose, while cellular respiration releases energy from glucose.

Question 12

A plant is exposed to only green light. What is the most likely outcome for its rate of photosynthesis?

Accepted Answer

It will decrease because chlorophyll reflects green light.

Question 13

Which of the following best describes the fate of G3P produced in the Calvin cycle?

Accepted Answer

Some G3P is used to synthesize glucose and other organic molecules.

Question 14

Which of the following is true regarding the absorption spectrum of chlorophyll?

Accepted Answer

Chlorophyll absorbs light most efficiently in the blue and red regions.

Question 15

Which of the following is a correct statement about the location of ATP synthase in plant cells?

Accepted Answer

ATP synthase is located in the thylakoid membrane of chloroplasts.

Question 16

Which of the following best explains why increased atmospheric $$CO_2$$ can affect C3 plants differently than C4 plants?

Accepted Answer

C3 plants are more limited by $$CO_2$$ concentration due to photorespiration.

Question 17

Which of the following is the correct sequence of events in non-cyclic photophosphorylation?

Accepted Answer

Photosystem II → Electron transport chain → Photosystem I → NADPH formation

Question 18

Which of the following best describes the role of accessory pigments in photosynthesis?

Accepted Answer

They absorb light in regions not absorbed by chlorophyll and transfer energy to chlorophyll.

Question 19

Which of the following is reduced during the light reactions of photosynthesis?

Accepted Answer

NADP$$^+$$

Question 20

A scientist measures the oxygen output of a plant under different wavelengths of light. Which type of experiment is this most likely to be?

Accepted Answer

Action spectrum

Photosynthesis: Light Reactions, Calvin Cycle, and Adaptations

Study Guide - Practice Questions