1.9 Active Transport

Question 1

Define active transport

Answer 1

The movement of substances from a dilute solution to a more concentrated solution against a concentration gradient, requiring energy from respiration

Question 2

Give an example of how active transport is used in plants

Answer 2

Plants use active transport to move mineral ions from the soil to the roots against a concentration gradient

Question 3

How is active transport used in the kidneys?

Answer 3

Sugar is actively absorbed out of the gut and kidney tubules and into the blood

Question 4

How is active transport used by crocodiles?

Answer 4

Some crocodiles have salt glands in their tongues. These remove excess salt from the body against the concentration gradient by active transport. This enables crocodiles to live in estuaries and the sea

Question 5

Describe how active transport works in a cell

Answer 5

Useful molecule binds to transport protein in cell membrane. Transport protein changes shape and moves useful molecule across membrane into cell,
against concentration gradient. Useful molecule is released, transport protein returns to original
position.