Maintaining a compartment with conditions different from the cytosol.Making every compartment chemically identical at all times.Preventing every type of exchange permanently.

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Which observation fits facilitated diffusion?

ATP-coupled pumping against an ion gradient.A vesicle engulfs a bacterium.A specific carrier moves a polar solute down its gradient.

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Which extra feature is needed to explain sustained net uptake against a gradient?

Random motion only.Energy coupling to a suitable transport protein.A larger concentration gradient in the opposing direction, with no energy source.

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Which process releases a secreted protein from a vesicle?

Exocytosis.Simple diffusion through lipid tails.Osmosis.

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Question 1 of 5

Explain the mosaic

Explain how phospholipids, proteins, glycolipids, glycoproteins and cholesterol contribute to cell membrane function.

Assign a distinct role to every named component.

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wise otter / H1 BiologyOfficial 2027 syllabus