Which best describes how energy from the sun helps to maintain life on Earth?

• A. It is stored in the nucleus of plant cells for later use.
• B. It is captured by plants during photosynthesis to produce glucose, which serves as an energy source for most living organisms.
• C. It is used by animals to synthesize chlorophyll.
• D. It directly powers cellular respiration in animal cells.

Answer: (B)

Verified step by step guidance

1. Step 1: Begin by understanding the role of the sun's energy in biological processes. The sun provides light energy, which is essential for photosynthesis, a process carried out by plants, algae, and some bacteria.
2. Step 2: Explain photosynthesis. During photosynthesis, light energy is captured by chlorophyll in plant cells and converted into chemical energy stored in glucose molecules. The chemical equation for photosynthesis is: ${6\mathrm{CO}2}_{+}$.
3. Step 3: Highlight the importance of glucose. Glucose produced during photosynthesis serves as an energy source for plants and is passed along the food chain to other organisms, including animals, through consumption.
4. Step 4: Clarify why the other options are incorrect. Energy from the sun is not stored in the nucleus of plant cells, nor is it directly used by animals to synthesize chlorophyll or power cellular respiration. Cellular respiration in animals relies on glucose, which originates from photosynthesis.
5. Step 5: Conclude by emphasizing the correct answer. The sun's energy is captured by plants during photosynthesis to produce glucose, which serves as the primary energy source for most living organisms, maintaining life on Earth.