Question 1

Which of the following best describes a photoautotroph?

Accepted Answer

An organism that uses light energy to synthesize organic compounds from inorganic substances.

Question 2

Where within a leaf are chloroplasts primarily located?

Accepted Answer

In the mesophyll cells, which are specialized for photosynthesis.

Question 3

Which equation correctly represents the overall process of photosynthesis?

Accepted Answer

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

Question 4

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

Accepted Answer

To generate ATP and NADPH for the Calvin cycle.

Question 5

Why do plants use multiple types of photosynthetic pigments?

Accepted Answer

To absorb a broader range of wavelengths of light for more efficient photosynthesis.

Question 6

Which of the following is a direct product of the Calvin cycle?

Accepted Answer

G3P (glyceraldehyde-3-phosphate)

Question 7

How is oxygen produced during photosynthesis?

Accepted Answer

By splitting water molecules during the light reactions.

Question 8

What is the role of the electron transport chain in the light reactions?

Accepted Answer

It transfers electrons from water to NADP+, forming NADPH.

Question 9

Which photosystem is associated with the P700 reaction center?

Accepted Answer

Photosystem I

Question 10

What is chemiosmosis in the context of photosynthesis?

Accepted Answer

The movement of protons across the thylakoid membrane to generate ATP.

Question 11

Which of the following best explains the importance of photosynthesis to life on Earth?

Accepted Answer

It provides oxygen and organic molecules that support most life forms.

Question 12

Which of the following is a reactant in the Calvin cycle?

Accepted Answer

NADPH

Question 13

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

Accepted Answer

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

Question 14

Which of the following statements about the structure of a chloroplast is correct?

Accepted Answer

The thylakoid membranes contain chlorophyll and are the site of the light reactions.

Question 15

Which of the following best describes the flow of electrons during the light reactions?

Accepted Answer

From water to NADP+ via photosystem II and photosystem I.

Question 16

What is the main purpose of the Calvin cycle?

Accepted Answer

To fix carbon dioxide into organic molecules like glucose.

Question 17

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

Accepted Answer

Glucose

Question 18

A mutation prevents a plant from producing P680. What process would be directly affected?

Accepted Answer

The splitting of water and oxygen production in photosystem II.

Question 19

Which of the following best describes the relationship between the light reactions and the Calvin cycle?

Accepted Answer

The light reactions provide ATP and NADPH to power the Calvin cycle.

Question 20

Which of the following is a real-world consequence if photosynthesis stopped occurring on Earth?

Accepted Answer

Atmospheric oxygen levels would decrease, threatening aerobic life.

Photosynthesis: Using Light to Make Food (Chapter 7 Study Guide)

Study Guide - Practice Questions