Question

questions 1 through 3 refer to the following. the diagram below shows a simplified carbon cycle.
2 mark for review
based on the diagram above, which of the following processes reduces the amount of carbon dioxide in the atmosphere?
a photosynthesis
b cellular respiration
c decomposition
d burning of fossil fuels

Explanation:

To determine which process reduces atmospheric \( \text{CO}_2 \), we analyze each option:

• Option A (Photosynthesis): Plants use \( \text{CO}_2 \) from the atmosphere to produce glucose (\( \text{6CO}_2 + \text{6H}_2\text{O}

ightarrow \text{C}_6\text{H}_{12}\text{O}_6 + \text{6O}_2 \)), so this removes \( \text{CO}_2 \) from the atmosphere.

• Option B (Cellular Respiration): Organisms release \( \text{CO}_2 \) (e.g., \( \text{C}_6\text{H}_{12}\text{O}_6 + \text{6O}_2

ightarrow \text{6CO}_2 + \text{6H}_2\text{O} \)), increasing atmospheric \( \text{CO}_2 \).

• Option C (Decomposition): Decomposers break down organic matter, releasing \( \text{CO}_2 \) (increases atmospheric \( \text{CO}_2 \)).
• Option D (Burning of Fossil Fuels): Releases \( \text{CO}_2 \) (increases atmospheric \( \text{CO}_2 \)).

Only photosynthesis reduces atmospheric \( \text{CO}_2 \).

Answer:

A. Photosynthesis