Question 1

Which of the following best describes the overall chemical equation for photosynthesis in plants?

Accepted Answer

$$6CO_2 + 6H_2O \rightarrow C_6H_{12}O_6$ + 6O_2$$

Question 2

Why is photosynthesis considered essential for life on Earth?

Accepted Answer

It produces oxygen and organic molecules that serve as the basis for most food chains.

Question 3

Which organelle is the primary site of photosynthesis in eukaryotic plant cells?

Accepted Answer

Chloroplast

Question 4

What is the role of stomata in photosynthesis?

Accepted Answer

They allow the exchange of gases, such as $$CO_2$$ and $$O_2$$, between the plant and the environment.

Question 5

Which pigment is primarily responsible for capturing light energy during photosynthesis?

Accepted Answer

Chlorophyll

Question 6

During the light reactions of photosynthesis, what is the main function of Photosystem II?

Accepted Answer

It uses light energy to split water, releasing oxygen and providing electrons for the electron transport chain.

Question 7

Which molecule acts as the final electron acceptor in the light reactions of photosynthesis?

Accepted Answer

NADP$$^+$$

Question 8

What is the primary purpose of the Calvin Cycle in photosynthesis?

Accepted Answer

To use ATP and NADPH to convert $$CO_2$$ into glucose.

Question 9

Which of the following best explains why plants appear green?

Accepted Answer

Chlorophyll reflects green wavelengths of light while absorbing others.

Question 10

In the context of energy flow in ecosystems, what is the relationship between photosynthesis and cellular respiration?

Accepted Answer

Photosynthesis stores energy in glucose, while cellular respiration releases that energy for cellular work.

Question 11

Which domain contains organisms that perform photosynthesis in the cytoplasm rather than in chloroplasts?

Accepted Answer

Domain Bacteria

Question 12

What is the main source of electrons for the light reactions in photosynthesis?

Accepted Answer

Water ($$H_2O)$$

Question 13

Which of the following is a direct product of the light reactions that is used in the Calvin Cycle?

Accepted Answer

NADPH

Question 14

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

Accepted Answer

Photosynthesis will decrease because green light is mostly reflected, not absorbed.

Question 15

Which of the following best describes the role of ATP synthase in photosynthesis?

Accepted Answer

It produces ATP from ADP and inorganic phosphate using the proton gradient across the thylakoid membrane.

Question 16

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

Accepted Answer

Glucose

Question 17

If a plant's stomata are closed during the day to conserve water, which process is most directly affected?

Accepted Answer

Carbon dioxide uptake for the Calvin Cycle

Question 18

Which of the following statements about the Calvin Cycle is correct?

Accepted Answer

It uses ATP and NADPH to convert $$CO_2$$ into organic molecules.

Question 19

Which of the following is a real-world consequence of the process of photosynthesis?

Accepted Answer

It provides the oxygen necessary for aerobic respiration in animals.

Question 20

Which of the following best explains why photosynthetic organisms are considered producers in food chains?

Accepted Answer

They convert solar energy into chemical energy stored in organic molecules.

Photosynthesis: The Energy of Life (Part 2)

Study Guide - Practice Questions