Active transport

Question 1

Root hair cells take in minerals and water

Answer 1

1) cell on plant roots grow into “hairs” which stick out into the soil
2) Each branch of a root will be covered in millions of these microscopic hairs which gives plant large SA for absorbing mineral and water ions from soil
3) plants need mineral ions for healthy growth
4) concentration of minerals is usually higher in root hair cells than soil around them
5) root hairs can’t use diffusion to take up minerals from soil

Question 2

How do root hairs take in minerals ?

Answer 2

Minerals should move out of root hairs if they did follow the rules of diffusion ( they don’t )

They use active transport which allows the plant to absorb minerals from a very dilute solution against a concentration gradient. Essential for growth but AT needs energy from respiration to make it work.

Question 3

Define active transport

Answer 3

Active transport is the movement of molecules or ions across a cell membrane from a region of lower concentration to a region of higher concentration

Question 4

Active transport in humans

Answer 4

Active transport used in gut when there is low concentration of nutrients in gut but higher concentration of nutrients in blood.

1) High concentration of glucose and amino acids in gut which diffuse naturally into blood
2) Sometimes there’s low concentration in gut then there is in blood = concentration gradient wrong way

5) active transport allows nutrients to be taken into the blood despite concentration gradient being wrong way

6) means glucose can be taken into bloodstream when its concentration in the blood is already higher than in gut then can be transported to cells where its used for respiration.