Topics:
Animal Physiology, Animal Refresher
True Statements About Mitochondria
Which of the following statements is/are true about mitochondria?
- All the above — Correct Answer
- It is a double membrane bound organelle and site of cellular respiration only
- It is known as powerhouse of the cell only
- It shows maternal inheritance only
Explanation:
Correct Answer: All the above
All three statements about mitochondria are correct:
Key Facts About Mitochondria
- Double membrane-bound + site of cellular respiration: Mitochondria have an outer membrane and a highly folded inner membrane (cristae). The inner membrane is the site of the electron transport chain (ETC) and ATP synthase (oxidative phosphorylation). The matrix contains enzymes for the Krebs cycle and β-oxidation of fatty acids.
- Powerhouse of the cell: Mitochondria produce ~36–38 ATP molecules per glucose molecule via aerobic respiration — far more than anaerobic glycolysis (net 2 ATP). Hence the name 'powerhouse.'
- Maternal inheritance: The mitochondrial genome (mtDNA) is inherited exclusively from the mother. During fertilization, the egg's mitochondria are retained while sperm mitochondria are actively destroyed. This forms the basis of mitochondrial DNA analysis for maternal lineage tracing.
Additional Mitochondrial Features
- Contain their own 70S ribosomes and circular DNA (evidence of endosymbiotic origin).
- Can replicate independently via binary fission.
- Number: varies from 1 (in some unicellular organisms) to >2000 per cell in high-energy cells (heart, liver).
📚 About this Topic — Animal Physiology
This multiple choice question is from Animal Physiology, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Physiology to strengthen your preparation.
