Near the end of digestion, cells lining the small intestine continue to move glucose into the blood, although the glucose concentration is lower in the intestine than in the blood.
The lining cells contain many mitochondria.
Which statement explains why these mitochondria are important?
They make random movement directional, allowing glucose to diffuse from a lower to a higher concentration
They release energy by respiration so carrier proteins can move glucose into the blood
They form protein channels in the cell membrane, allowing glucose to cross without respiration
They lower the water potential of the blood, so glucose crosses the cell membrane by osmosis
194 exam-style questions on OCR GCSE Biology 2.1 Supplying the cell, covering 2.1.1 Transport across cell membranes, 2.1.2 Mitosis and the cell cycle, 2.1.3 Importance of cell differentiation, and 2.1.4 Stem cells. Each one has a worked solution and a mark scheme showing where the marks go.