36 exam-style questions on Organelles and compartmentalization — topic B2.2 of Form and function in the IB Biology syllabus — with answers and explanations. Samples below; the full set is free with an account.
Which organelle is the primary site of aerobic respiration and ATP synthesis in eukaryotic cells?
Answer: Mitochondrion
Mitochondria carry out the Krebs cycle and oxidative phosphorylation, producing most of the cell's ATP.
Ribosomes attached to the rough endoplasmic reticulum are primarily involved in synthesising proteins that are
Answer: secreted or membrane-bound
The rough ER produces proteins destined for secretion, lysosomes or membranes; free ribosomes make proteins used in the cytosol.
Which sequence correctly traces a secreted protein through the endomembrane system?
Answer: Rough ER → Golgi apparatus → secretory vesicle → plasma membrane
Proteins are made on the rough ER, modified and packaged in the Golgi, then carried in secretory vesicles that fuse with the plasma membrane.
A structure present in a plant cell but absent from a typical animal cell is the
Answer: chloroplast
Chloroplasts (and a cellulose cell wall and large permanent vacuole) are found in plant cells but not in typical animal cells.
Lysosomes contribute to cell function by
Answer: holding hydrolytic enzymes
Lysosomes hold hydrolytic (digestive) enzymes at low pH used to break down engulfed material and recycle organelles.
Which observation supports the endosymbiotic theory for the origin of mitochondria and chloroplasts?
Answer: They possess their own circular DNA and 70S ribosomes
Their own circular DNA, 70S (prokaryote-type) ribosomes and double membranes indicate descent from free-living bacteria engulfed by an ancestral cell.
That was 6 of 36 Organelles and compartmentalization questions.
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36 Organelles and compartmentalization questions — free with an account. Spaced repetition, streaks and full exam simulations included.
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