What is the primary purpose of cellular respiration in eukaryotic cells?

• A. To store genetic information
• B. To produce ATP by breaking down glucose
• C. To synthesize glucose from carbon dioxide and water
• D. To convert light energy into chemical energy

Answer: (B)

Verified step by step guidance

1. Understand the concept of cellular respiration: Cellular respiration is a metabolic process that occurs in eukaryotic cells to convert biochemical energy from nutrients, primarily glucose, into adenosine triphosphate (ATP), which is the energy currency of the cell.
2. Identify the main stages of cellular respiration: Cellular respiration consists of three main stages—glycolysis, the citric acid cycle (Krebs cycle), and oxidative phosphorylation (electron transport chain). Each stage contributes to the production of ATP.
3. Recognize the role of glucose: Glucose is broken down during glycolysis into pyruvate, which is further processed in the citric acid cycle and electron transport chain to produce ATP. This process also releases carbon dioxide and water as byproducts.
4. Clarify the purpose of ATP: ATP is used by cells to perform various functions, such as muscle contraction, active transport, and biochemical reactions. Cellular respiration ensures a continuous supply of ATP to meet the energy demands of the cell.
5. Eliminate incorrect options: Cellular respiration does not store genetic information (this is the role of DNA), synthesize glucose (this occurs in photosynthesis), or convert light energy into chemical energy (also a function of photosynthesis). Its primary purpose is to produce ATP by breaking down glucose.