Active cell physiology

Question 1

diffusion definition

Answer 1

the movement of molecules from a high concentration to a low concentration

Question 2

osmosis definition

Answer 2

the movement of water across a membrane to equalize solute concentration

Question 3

isotonic

Answer 3

• the EFC and IFC are in balance with the 2 solutions
• concentration is the same on both sides

Question 4

hypertonic

Answer 4

EFC loses water making the concentration of solutes higher compared to IFC

Question 5

hypertonic to isotonic

Answer 5

IFC decreases in volume as water moves to higher concentration of solutes in order to restore isotonic state (equal concentration)

Question 6

hypotonic

Answer 6

concentration lowers in EFC as solutes have more space

Question 7

hypotonic to isotonic

Answer 7

water will drastically move into IFC to even concentration

Question 8

chemical gradient definition

Answer 8

uneven distribution of molecules across the membrane

Question 9

what is the sodium-potassium exchange pump

Answer 9

An active pump that uses ATP to move 3 sodium ions out and 2 potassium ions inside the cell. This creates a chemical gradient for both molecules as well as maintaining a electrical gradient.

Question 10

what is the resting membrane potential

Answer 10

-70 mV (more negatively charged inside the cell.

Question 11

definition of depolarization

Answer 11

positive ions enter the cell
- acts as a signaling event for excited cells

Question 12

definition of repolarization

Answer 12

positive ions are removed
- to return the resting membrane potential