B2.1.3 Active Transport

Question 1

Define active transport

Answer 1

The movement of substances from an area of low concentration to high against a concentration gradient using energy

Question 2

Key features of active transport

Answer 2

Particles are transported against concentration gradient
ATPrequired from respiration
Makes use of carrier proteins in cell membrane

Question 3

What are carrier proteins

Answer 3

Special proteins that span the width of the cell membrane

Question 4

How does carrier proteins use energy

Answer 4

A particular molecule that the cell requires, bonds to a specific carrier protein
Energy is transferred from an energy store to the proteins so it can change shape or rotate
Carrier protein transports molecule into cell

Question 5

Active transport example

Answer 5

Digestion:
Carbs broken down into glucose in small intestine
Glucose is actively transported into bloodstream through villi
Blood takes glucose to wherever it is needed in the body

Question 6

Another example of active transport

Answer 6

Neve cells:
Carrier protein actively pumps sodium ions out of the cell
At the same time potassium ions are pumped back in
Sodium potassium pump plays an important role in creating never impulses

Question 7

How do plants use active transport

Answer 7

Plants need nitrate ions to make proteins for growth.
There’s normally a lower concentration of nitrate ions in the soil water surrounding the roots than in the plant.
Plant root hair cells use active transport to move these ions across cell membrane and into root cell