Cell Organelles (ER, Golgi, Lysosomes, Mitochondria, Plastids, Vacuoles) MCQs

Q1. A sprinter's thigh muscles burn glucose furiously during a 100 m dash and demand a steady flood of usable energy; which organelle releases that energy as ATP?

• A.Golgi apparatus
• B.Lysosome
• C.Ribosome
• D.Mitochondrion

Answer: D. Mitochondrion

Cellular respiration that converts glucose energy into ATP happens in the mitochondrion, so the muscle's energy supply comes from mitochondria.

Q2. A textbook calls one organelle the 'powerhouse of the cell' because it churns out the molecule cells spend as fuel; what is that fuel molecule?

• A.ATP
• B.Glucose
• C.Chlorophyll
• D.DNA

Answer: A. ATP

Mitochondria release energy by oxidising glucose and store it as ATP, the cell's spendable energy currency.

Q3. A heart-muscle cell never rests and so contains thousands of mitochondria, while a barely active skin cell has far fewer; what does this difference in mitochondrial number reveal?

• A.Mitochondria multiply only in skin cells
• B.Heart cells use mitochondria for storage, not energy
• C.Cells with higher energy demand carry more mitochondria
• D.Larger cells always have fewer mitochondria

Answer: C. Cells with higher energy demand carry more mitochondria

Mitochondria supply ATP, so tissues that work constantly, like cardiac muscle, hold many more mitochondria than low-energy tissues such as resting skin.