The diagram shows oxygen concentration inside and outside a red blood cell in a capillary in a respiring muscle. Oxygen concentration inside the cell is 2% and outside is 8%. In which direction will oxygen diffuse and why?

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Question

The diagram shows oxygen concentration inside and outside a red blood cell in a capillary in a respiring muscle. Oxygen concentration inside the cell is 2% and outside is 8%. In which direction will oxygen diffuse and why?

Accepted Answer

Into the cell, because diffusion occurs from a region of higher concentration to lower concentration — Award 1 mark for recognizing oxygen moves into the cell (from 8% to 2%) down the concentration gradient. A is incorrect — diffusion occurs from higher to lower concentration, not lower to higher. B is incorrect about direction — oxygen is higher outside (8%) than inside (2%). D is incorrect — cell membranes are permeable to oxygen.

Answer

Into the cell, because diffusion occurs from a region of lower concentration to higher concentration

Answer

Out of the cell, because diffusion occurs from a region of higher concentration to lower concentration

Answer

Into the cell, because diffusion occurs from a region of higher concentration to lower concentration

Answer

No net movement will occur because the cell membrane is impermeable to oxygen

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