1.4 Osomosis

Question 1

What is osmosis

Answer 1

Osmosis is the net movement of water molecules across a partially permeable membrane

from a region of higher water concentration, to a region of lower water concentration.

Question 2

True or false? Osmosis is a special form of diffusion.

True

False

Answer 2

true

Question 3

In living organisms, the partially permeable membrane is usually the _______

Answer 3

cell membrane

Question 4

True or false? During osmosis, water moves against the concentration gradient.

Justify your answer

Answer 4

False

During osmosis, water moves down the concentration gradient (from high to low) meaning flows through it

not against it (from low to high).

Question 5

What would happen to red blood cells if they were placed in pure water?

Justify your ans.

Answer 5

When red blood cells are placed in a hypotonic solution (higher concentration outside the cell)

water moves into the cell because of osmosis.

As water enters, the cell swells and increases internal pressure.

Since RBCs don’t have a rigid cell wall, this pressure can cause the cell to burst.

Question 6

outside the cell there is more particles than inside the cell

in which direction would you expect the water to move in

Answer 6

There’s a greater concentration of water particles outside the cell

so the water molecules would move, via osmosis

from the higher concentration to lower

outside –> inside