Movement Into and Out of Cells

Question 1

Diffusion

Answer 1

• moves down the concentration gradient (high to low)
• for solutes
• bigger gradient = faster diffusion
• uses kinetic energy

Question 2

Osmosis

Answer 2

• moves down the concentration gradient (high water potential to low water potential)
• semi-permeable membrane
• kinetic energy

Question 3

Active Transport

Answer 3

• moves against the concentration gradient (low to high)
• needs cell membrane
• energy from respiration
• plants

Question 4

Osmosis: animal cell

Answer 4

Hypotonic (water moves in) = diluted, lysed = burst

Isotonic (water moves in and out) = normal

Hypertonic (water moves out) = concentrated, shrivelled = shrink

Question 5

Osmosis: plant cell

Answer 5

Hypotonic (water moves in) = turgid, cell wall stops from bursting

Isotonic (water moves in and out) = flaccid

Hypertonic (water moves out) = plasmolysed (cytoplasm and cell membrane moves away from the cell wall)

Question 6

No net movement

Answer 6

Water concentration is the same

Question 7

Osmosis Chip Experiment (living)

Answer 7

Chips into sucrose solution, tap water or air, 30 mins, then weigh

% change = change (mass)/starting (mass) x 100%

Question 8

Osmosis Visking Tubing experiment (non-living)

Answer 8

• the tube has a sugar solution, pure water on the outside
• water is drawn in

Question 9

Diffusion experiment (surface area)

Answer 9

3 agar jelly (different sizes) dyed with potassium permanganate into HCL, cut in half and measure

Question 10

Diffusion: surface area

Answer 10

Increase surface area = more diffusion of particles, but no change in speed (surface area : volume ratio)