Osmosis

Question 1

What is osmosis

Answer 1

The diffusion if water particles across a partially permeable membrane from an area of higher concentration to an area of lower concentration

Question 2

What is a water potential

Answer 2

A water potential is the likelihood that water molecules diffuse into or out of a solution

Question 3

Tell me about pure water and the water potential

Answer 3

Has a water potential of zero adding solutes will lower the water potential so it is always negative. The more negative the solution is the stronger the concentration of solutes in the solution

Question 4

What is it called when two solutions have the same water potential

Answer 4

Isotonic, therefore there is no net movement of water molecules because there is no difference in water potential between the cell and the surrounding solution

Question 5

What happens if the cell is placed in a solution that has a higher water potential

Answer 5

It will swell as water moves in by osmosis - hypotonic

Question 6

What happens if the cell is place in a solution of lower water potential

Answer 6

It was shrink as water moves out by osmosis - hypertonic

Question 7

What is it called when water moves out of the cell

Answer 7

Hypertonic

Question 8

What is it called when water moves into the cell

Answer 8

Hypotonic

Question 9

What are the factors that affect the rate of osmosis and explain

Answer 9

The water potential gradient - the higher the water potential gradient, the fast per the rate of osmosis, slows down over time
The thickness of the exchange surface - the thinner the exchange surface, the faster osmosis will be
The surface area of exchange surface - the larger the surface area the faster the rate of osmosis

Question 10

How would you investigate water potential

Answer 10

Make serial dilutions
Then measure the mass of the potatoes, cut the potatoes into exact identical sizes about 1cm in diameter
Place one group in a sucrose solutions and leave for 20 minutes
Remove the potatoes from the solutions and pat dry gently with a paper towel
Weigh again and calculate a percentage change
Produce a calibration curve to determine the water potential