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

Question 1

Which of the following organisms can perform photosynthesis using chloroplasts?

Accepted Answer

Plants

Question 2

Where do the light-dependent reactions of photosynthesis occur in eukaryotic cells?

Accepted Answer

In the thylakoid membranes of the chloroplast

Question 3

What is the main purpose of the light-dependent reactions in photosynthesis?

Accepted Answer

To convert sunlight energy into chemical energy in the form of ATP and NADPH

Question 4

Which molecule is a direct product of the light-dependent reactions and is used in the Calvin cycle?

Accepted Answer

NADPH

Question 5

During the Calvin cycle, what is the source of carbon for building sugars?

Accepted Answer

Carbon dioxide ($$CO_2)$$

Question 6

Which of the following best describes the overall equation for photosynthesis?

Accepted Answer

$$6CO_2 + 6H_2O + 	ext{light energy} ightarrow C_6H_{12}O_6$ + 6O_2$$

Question 7

Which of the following is a byproduct of the light-dependent reactions?

Accepted Answer

Oxygen ($$O_2)$$

Question 8

A scientist exposes a plant to light but removes all $$CO_2$$ from its environment. Which process will be directly affected?

Accepted Answer

Calvin cycle (carbon fixation)

Question 9

Which of the following statements about prokaryotic photosynthesis is correct?

Accepted Answer

Some bacteria can perform photosynthesis without chloroplasts

Question 10

If a plant's thylakoid membranes are damaged, which process will be most directly affected?

Accepted Answer

Light-dependent reactions

Question 11

Which of the following best explains why oxygen is released during photosynthesis?

Accepted Answer

Oxygen is produced when water is split during the light-dependent reactions

Question 12

A plant is placed in a sealed container with plenty of water and sunlight but no $$CO_2. $$Which of the following will occur?

Accepted Answer

The light-dependent reactions will occur, but the Calvin cycle will stop

Question 13

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

Accepted Answer

Glucose

Question 14

Why is the Calvin cycle also called the 'light-independent reactions'?

Accepted Answer

It does not require direct sunlight to proceed

Question 15

Which of the following best describes the role of NADPH in photosynthesis?

Accepted Answer

It carries high-energy electrons to the Calvin cycle

Question 16

A mutation prevents a plant from producing ATP during the light-dependent reactions. What is the most immediate consequence?

Accepted Answer

The Calvin cycle cannot proceed

Question 17

Which of the following is a correct sequence of events in photosynthesis?

Accepted Answer

Light-dependent reactions produce ATP and NADPH, which are used in the Calvin cycle

Question 18

Which of the following best explains why plants are considered autotrophs?

Accepted Answer

They produce their own food using sunlight, water, and $$CO_2$$

Question 19

In a real-world scenario, why might algae blooms occur in lakes with high nutrient runoff?

Accepted Answer

Algae require nutrients and sunlight for photosynthesis, so excess nutrients promote rapid growth

Question 20

Which of the following is a multi-step process that integrates both phases of photosynthesis?

Accepted Answer

Sunlight excites electrons in chlorophyll, leading to ATP and NADPH production, which then power the Calvin cycle to synthesize glucose from $$CO_2$$

Photosynthesis: Mechanisms and Overview

Study Guide - Practice Questions