Sequence the following stages of cellular respiration: 1. Electron Transport Chain 2. Glycolysis 3. Krebs Cycle 4. Pyruvate Oxidation
2 → 4 → 3 → 1
Aerobic cellular respiration breaks down glucose in a fixed order of stages.
Glycolysis (2) comes first: in the cytoplasm, one glucose molecule is split into two molecules of pyruvate, with a small net gain of ATP and NADH.
Pyruvate Oxidation (4) follows: pyruvate enters the mitochondrion and is converted into acetyl-CoA, releasing CO2 (the link reaction).
Krebs Cycle (3) is next: acetyl-CoA is oxidised in the mitochondrial matrix, producing CO2, NADH, FADH2 and some ATP.
Electron Transport Chain (1) is last: on the inner mitochondrial membrane, NADH and FADH2 pass electrons to oxygen, and most of the ATP is made by oxidative phosphorylation.
Hence, the correct sequence is 2 → 4 → 3 → 1 (Glycolysis → Pyruvate Oxidation → Krebs Cycle → Electron Transport Chain).
Important Questions from Life Processes
Which one of the following is the process involved in photosynthesis?
Which element is needed by the thyroid gland to produce thyroxine hormone?
Identify the correct match of plant hormones with their functions.
What is required for the synthesis of thyroxin hormones?
Which of the following receptors help in the detection of taste?
