Water and sodium Balance

Question 1

How much percentage of water is body weight and how is it split intracellularly and extracellularly?

Answer 1

60% of body weight is water
Intracellularly = 2/3
Extracellularly = 1/3

Question 2

What separates the intracellular and extracellular compartments?

Answer 2

Plasma membrane

Question 3

What two regions is the extracellular compartment divided into?

Answer 3

Extravascular (interstitial)

Intravascular (plasma)

Question 4

What are channels that are through the plasma membrane of cells that allows the passage of water between the intracellular and extravascular compartments?

Answer 4

Aquaporins

Question 5

What 2 forces occur in response to the flow of water across one or the other partition?

Answer 5

Hydrostatic pressure

Osmotic pressure

Question 6

What is the stressed volume of water interacting with the capacitance of the compartment

Answer 6

Hydrostatic pressure

Question 7

What is the number of “solute particles” (e.g. Na+, K+, Cl-, etc.) dissolved within the water, to which the partition is impermeable? Also opposes osmotic flow across a semi-permeable membrane

Answer 7

Osmotic Presssure

Question 8

What causes solute to move from the compartment with higher concentration into the compartment with lower concentration

Answer 8

Diffusion force

Question 9

What causes water to move from the compartment with a lesser amount of solute (“more dilute”) into the compartment with a greater amount of solute (“less dilute”)

Answer 9

Osmotic force

Question 10

What is called when osmolality is greater (more solute, less dilute)

Answer 10

Hyperosmotic

Question 11

What is it called when osmolality is less (less solute, more dilute)

Answer 11

Hypoosmotic

Question 12

What will exist whenever the osmotic pressure is not the same between the two compartments?

Answer 12

Osmotic gradient

Question 13

What refers to the osmolality of the extracellular compartment relative to the intracellular, causing water to move into or out of cells to change the cellular volume

Answer 13

Tonicity

Question 14

What is Hypotonic interstitium?

Answer 14

Less concentrated (more dilute, low osmolarity) interstitium
water flows from interstitium into cells causing them to swell

Question 15

What is Hypertonic interstitium?

Answer 15

More concentrated (less dilute, high osmolarity)
water flows out of cell into interstitium causing cells to shrink

Question 16

What is proportional balance between water and solute

Answer 16

Osmolarity

Question 17

What would alter osmolarity?

Answer 17

a gain or loss in water or solute

Question 18

What is the movement of water out of capillaries, from plasma into the surrounding interstitium?

Answer 18

Filtration

Question 19

What is the movement of water into capillaries, from the surrounding interstitium

Answer 19

Reabsorption

Question 20

What causes water to be filtered from plasma?

Answer 20

Capillary hydrostatic pressure

Question 21

What is the equilibrium called that reflects the relative balance between the hydrostatic and oncotic pressure gradients

Answer 21

Starling’s equilibrium