GCSE Biology B.1

Question 1

What is diffusion

Answer 1

Diffusion is the net movement of particles from an area of high concentration to an area of low concentration

Question 2

What affects the rate of diffusion

Answer 2

Temperature: particles move faster
Concentration gradient: the rate will be faster if there is a greater difference in concentration
Distance: less distance to travel increases the rate

Question 3

What effects rate of diffusion in cells

Answer 3

Surface area: more particles move in and out at once
Being thin: creates less distance between areas of diffusion
Ventilation(animal cells only): easier for particles to enter body if well ventilated
Efficient blood supply(animals only): constant supply of particles

Question 4

What is active transport

Answer 4

A process used by plants to transport minerals that requires energy and allows substances to be moved into cells against a concentration gradient

Question 5

What is osmosis

Answer 5

The movement of particles from a dilute solution to a concentrated solution through a partially permeable membrane

Question 6

What is an isotonic solution

Answer 6

The fluids have an equal concentration

Question 7

What is a hypotonic solution

Answer 7

The solution is more dilute

Question 8

What is hypertonic

Answer 8

The solution is more concentrated