The correct Answer is A-3, B-4, C-2, D-1
Explanation
Cellular respiration involves a series of metabolic reactions that convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products. This process can be aerobic (requiring oxygen) or anaerobic (without oxygen). Different organisms and cellular conditions lead to variations in the end products and sites of these reactions.
Statement-wise Analysis
- A. Yeast - 3. Produces Ethanol and CO₂
- Correct: Yeast performs anaerobic respiration, specifically alcoholic fermentation, in the absence of oxygen. During this process, glucose is broken down into ethanol and carbon dioxide.
- B. Muscle cells (during heavy exercise) - 4. Produces Lactic acid
- Correct: During strenuous physical activity, when oxygen supply to muscle cells is insufficient, they switch to anaerobic respiration (lactic acid fermentation). This process breaks down glucose to produce lactic acid and a small amount of energy.
- C. Mitochondria - 2. Site of Krebs’ cycle
- Correct: The Krebs' cycle (also known as the citric acid cycle) is a key stage of aerobic respiration that occurs in the matrix of the mitochondria.
- D. Cytoplasm - 1. Site of Glycolysis
- Correct: Glycolysis, the initial stage of both aerobic and anaerobic respiration, takes place in the cytoplasm of the cell. During glycolysis, glucose is broken down into pyruvate.
Key Takeaway
Cellular respiration pathways vary based on oxygen availability and organism type, with glycolysis occurring in the cytoplasm, the Krebs' cycle in mitochondria, and anaerobic processes like alcoholic fermentation (yeast) and lactic acid fermentation (muscle cells) producing distinct end products.