94 exam-style questions on Cell structure — topic A2.2 of Unity and diversity in the IB Biology syllabus — with answers and explanations. Samples below; the full set is free with an account.
State the main function of the rough endoplasmic reticulum.
Answer: synthesis and transport of proteins
The rough ER is studded with ribosomes that synthesise proteins, which are then transported through the ER for processing.
Which organelle contains hydrolytic (digestive) enzymes used to break down materials within the cell?
Answer: lysosome
Lysosomes contain hydrolytic enzymes that digest worn-out organelles, ingested material and other macromolecules.
The organelle that modifies, sorts and packages proteins into vesicles for secretion is the:
Answer: Golgi apparatus
The Golgi apparatus processes proteins from the rough ER and packages them into vesicles for export or delivery within the cell.
Compared with a light microscope, an electron microscope allows small organelles to be seen mainly because it has a much higher:
Answer: resolution
The short wavelength of electrons gives far greater resolution (ability to distinguish close points), revealing detail a light microscope cannot.
An aseptate fungal hypha is a long tube of cytoplasm containing many nuclei and no cross walls. Why is this awkward for the cell theory?
Answer: It is not divided into separate units that each contain one nucleus.
The cell theory expects living material to be partitioned into discrete cells; a hypha, like a striated muscle fibre or a giant alga, is a working exception rather than a refutation. It does have a membrane and does have nuclei.
Paramecium lives in fresh water and continually gains water by osmosis. Which structure removes the excess?
Answer: The contractile vacuole.
A single cell has to carry out every function of life for itself; the contractile vacuole fills with water and expels it, which is the organism's osmoregulation. The food vacuole digests, the oral groove takes food in, and the cilia move the cell.
That was 6 of 94 Cell structure questions.
Practise all 94 freeStateAO1 · 1–2 marks
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DefineAO1 · 1–2 marks
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DistinguishAO2 · 1–4 marks
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94 Cell structure questions — free with an account. Spaced repetition, streaks and full exam simulations included.
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