Movement Across the Cell Membrane

Question 1

Diffusion is …

Answer 1

… the spreading out of particles from an area of higher concentration to an area of lower concentration.

Question 2

Diffusion doesn’t require ___ so it is a ___ process.

Answer 2

energy, passive

Question 3

Cell membranes are ___ permeable.

Answer 3

partially

Question 4

Osmosis is …

Answer 4

… 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 5

A concentration gradient is …

Answer 5

… higher concentration to lower concentration.

Question 6

Active transport is …

Answer 6

… the net movement of particles against a concentration gradient using energy transferred during respiration.

Question 7

Factors that affect rate of movement of substances into and out of cells are:

Answer 7

• Surface area to volume ratio - the greater the surface area per unit volume, the greater the rate of movement.
• Temperature - the greater the temperature, the greater the rate of movement.
• Concentration gradient - the wider the concentration gradient, the greater the rate of movement.