Contrast the processes of facilitated diffusion and active transport. (3 marks)
Facilitated diffusion involves the use of channel and carrier proteins to assist the diffusion of molecules or ions down a concentration gradient, as this is a passive process it does not require ATP (the universal energy currency). In contrast, active transport only involves carrier proteins and occurs against a concentration gradient, therefore this process requires energy from the hydrolysis of ATP.
HT
Related Biology A Level answers
All answers ▸what is a test cross used for and how do you know what genotypes to cross?
How is blood glucose regulated?
How can additional molecules or ions increase the activity of an enzyme?
Part of the retina of a young rat was removed and kept in the dark for two hours. This allowed the pigment in the rod cells to recover from bleaching caused by exposure to light. Suggest what happens in the rod cells during this two hours of darkness.