2 d Movement of substances into and out of cells

Question 1

What is diffusion

Answer 1

Random movement of particles from an area of a high concentration to an area of low concentration

Question 2

What restricts the free movement of particles

Answer 2

Cell membrane

Question 3

What is meant by partially permeable membrane

Answer 3

Allows only some molecules to cross easily, but others with difficulty

Question 4

Whats the simplest sort of selection of the partially permeable membrane

Answer 4

By the size of the molecule

Question 5

What does diffusion help with for organisms

Answer 5

• obtain many of their requirements
  -Get rid of waste products
  -Carry out gas exchange for respiration

Question 6

How does water move in and out of cells

Answer 6

Via osmosis

Question 7

What is osmosis

Answer 7

Movement of water from a region of higher water potential to lower water potential through a partially permeable membrane

Question 8

Why can water particles move through partially permeable membranes

Answer 8

Water molecules are smaller than solute molecules

Question 9

What would happen if an animal cell would be placed in a strong sugar solution

Answer 9

The water potential out the cell would be lower, it will loose the water by osmosis and shrivell up

Question 10

What would happen if an animal cell would be placed in distilled water

Answer 10

The water potential out the cell would be higher, it will gain water by osmosis and eventually burst

Question 11

Explain hypertonic solution

Answer 11

-Red blood cells have higher water potential than solution
-Net movement of water out
-Shrivelled cells

Question 12

Explain isotonic solution

Answer 12

-Water potential equal between red blood cell and solution
-No net movement of water
-Normal cells

Question 13

Explain hypotonic solution