Transport Across Membranes

Question 1

Diffusion

Answer 1

Movement of molecules from an area of high concentration to an area of low concentration until equilibrium is reached.

E.g Oxygen and carbon dioxide exchange in the lungs

Question 2

Osmosis

Answer 2

Special case of diffusion,
Movement of water across a semi-permeable membrane.
Water moves from areas of low solute concentration to high solute concentration.
E.g Water absorption in kidneys

Question 3

Active transport

Answer 3

Movement of molecules against the concentration gradient,Requiring atp
E.g Sodium potassium pump maintains cell membrane potential.

Question 4

Cell division-Mitosis

Answer 4

Mitosis is the process by which a cell divides to produce two identical daughter cells .

1.Prophase
2 Metaphase
3 Anaphase
4 Telephase
5 Cytokinesis