4.4 Active Transport

Question 1

What is active transport?

Answer 1

The movement of molecules or ions entering or exiting the cell from an area of lower concentration to an area of higher concentration using ATP and carrier proteins

Question 2

How does active transport transport a molecule?

Answer 2

~The molecule/ion binds to the receptor cells on the carrier protein
~ on the inside of the sale, ATP binds to the carrier protein causing it to split into ADP + inorganic phosphate
~ as a result, the protein molecule changes shape and opens to the opposite side of the membrane.
~ the molecule/ion is released to the other side of the membrane

Question 3

How does active transport differ from the other transport methods?

Answer 3

~ metabolic energy is needed therefore it is not a passive process
~ substances are moved against a concentration gradient (lower to higher)
~ the process is very specific, only certain substances can be transported
~ carrier proteins are involved being used as pumps

Question 4

What factors affect the rate of active transport?

Answer 4

~ the speed of individual carrier proteins -the faster they work, the faster, the rate of active transport
~ the number of carrier protein is present-the more protein is present, the faster, the rate of AT
~ the rate of respiration in the cell-if respiration is inhibited AT can’t take place
~ the availability of ATP