Topic 1 - Cell Transport

Question 1

What is diffusion

Answer 1

The net movement of particles from an area of high concentration to an area of low concentration

Question 2

Factors affecting diffusion

Answer 2

concentration gradient - the higher the difference the faster diffusion happens
distance - shorter distance = faster diffusion
temperature - hot particles move faster as they have more energy
surface area to volume ratio

Question 3

What is osmosis

Answer 3

Osmosis is the movement of water, from a high concentration to a low concentration across a partially permeable membrane

Question 4

What happens to an animal cell and a plant cell in high water concentration

Answer 4

when an animal cell is in a high concentration of water, water travels in to the cell through the partially permeable membrane by osmosis. The cell expands and bursts

However, in a plant cell the water moves in through osmosis across a semi-permeable membrane and the vacuole expands and the cell becomes turgid

Question 5

What happens to an animal cell and plant cell in a low water concentration

Answer 5

Animal cell - the water travels out of the cell by osmosis across the semi-permeable membrane. The cell becomes crenated.

Plant cell - the water travels out of the cell by osmosis across the semi-permeable membrane. the cell becomes Flacid

Question 6

How is the alveoli adapted to diffusion (4)

Answer 6

1. Moist, so gasses can dissolve
2. short distance, walls are 1 cell thick
3. large surface area to volume ratio
4. High concentration gradient to to breathing and capillaries (blood carrying and bringing gasses)

Question 7

What is active transport

Answer 7

Active transport is the process that transports particles from a low to high concentration using energy

Question 8

Where do cells get energy from to do active transport

Answer 8

mitochondria releases energy

Question 9

Respiration equation?

Answer 9

oxygen + glucose → water + carbon dioxide (+energy)

Question 10

How is the root hair cell adapted for active transport (3)

Answer 10

small distance
large surface area
many mitochondria

Question 11

How are the villi adapted for transport(5)

Answer 11

1. short diffusion distance,
2. high SA: VOLUME ration, increased by microvilli
3. More mitochondria for active transport
4. High concentration gradient, blood flow constantly takes away nutrients
5. intestine is very long, maximum diffusion