Diffusion, body fluid comp, transport

Question 1

What refers to the movement of water down a concentration gradient?

Answer 1

osmosis

Question 2

What causes osmotic flow?

Answer 2

number of particles (and not particle size) on one side of a permeable membrane

Question 3

Difference between osmolarity and osmolality?

Answer 3

osmolarity: Osm/L h2o
osmolality: Osm/kg h2o
osmolality will differ due to environmental conditions

Question 4

What describes the ability of solutions to cause cells to swell or shrink via osmosis?

Answer 4

Tonicity

Question 5

How do tonicity osmolarity differ?

Answer 5

tonicity describes the ability of a solution to make a cell swell or shrink and osmolarity the movement of water down a concentration gradient

Question 6

_____ solutions cause cells to swell;

_____ solutions cause cells to shrink

Answer 6

hypotonic; hypertonic

Question 7

how can cells recover from tonicity?

Answer 7

They retain or dump solutes in the cell to balance

Question 8

What are the three main fluid compartments?

Answer 8

Intracellular fluid, extracellular fluid, plasma

Question 9

how much ICF is in the body

Answer 9

28 L

Question 10

How much ECF is in the body

Answer 10

10.5 L

Question 11

How much plasma is in the body?

Answer 11

3.5 L

Question 12

What is the importance of plasma?

Answer 12

Plasma is important because the heart depends on it to generate cardiac output. Small changes in plasma volume can potentially cause large changes in arterial pressure.

Question 13

Why is the body pH kept within a narrow range?

Answer 13

H ion excess denatures proteins

Question 14

What are the body’s 3 primary acid defense mechanisms?

Answer 14

Proteins, phosphate, bicarbonate

Question 15

What is the main acid buffer system in cells (including RBCs)?

Answer 15

proteins

Question 16

How does a change in plasma pH affect K+ balance?

Answer 16

Plasma pH, if altered, can cause H+ ions to enter the plasma, which would kick out K+ ions to balance it. These potassium ions are dangerous for the heart’s function

Question 17

What is the main buffer system in the extracellular fluid?

Answer 17

bicarbonate

Question 18

What is diffusion and how is it affected by concentration, barrier permeability, and surface area?

Answer 18

Diffusion always goes from high to low concentration.

Diffusion increases with increased surface area and permeability

Question 19

Contrast the differences between pores, channels, and carriers

Answer 19

Pores- always open
Channels- gated
Carriers- binding step
Carriers fastest at low concentrations, slowest at high concentrations

Question 20

diffusion of molecules across the cell membrane via carrier proteins, channel proteins, or ions (e.g., glucose and fructose transport into cells via GLUT transporters)

Answer 20

facilitated diffusion

Question 21

The movement of molecules against their concentration gradient across a selectively permeable membrane. Requires ATP as an energy source.

Answer 21

primary active transport

Question 22

The use of the electrochemical gradient (e.g., generated by primary active transport) of one type of molecule to move another type of molecule against its gradient. Does not directly require ATP. Includes symporters (e.g., the sodium-glucose symporter) and antiporters (e.g., the sodium–hydrogen antiporter).

Answer 22

secondary active transport

Question 23

Main buffer in ICF

Answer 23

phosphate

Question 24

main buffer in ECF

Answer 24

bicarbonate

Question 25

main buffer in proteins

Answer 25

cells/blood