Osmosis

Question 1

osmosis

Answer 1

facilitated and passive diffusion
facilitated = aquaporin channels
passive = doesnt require energy moves down osmotic gradient

Question 2

osmotically active

Answer 2

non permeant solutes are osmotically active as they establish the osmotic gradient and promote the movement of water

Question 3

requirements for osmosis

Answer 3

conc dif between 2 sides of membrane

membrane impermeable to at least 1 solute

Question 4

osmotic pressure

Answer 4

the pressure generated when water moves across a semi permeable, non moveable membrane to equilibrate solvent concentration

Question 5

measuring osmotic pressure

Answer 5

measuring force generated

Question 6

osmotic pressure ratio

Answer 6

solute : solvent

i.e. total number of dissolved solute non permeant molecules in solution that determines the osmotic pressure

Question 7

osmolarity equation

Answer 7

osmolarity (OsM/L) = molarity (mol/L) x number of particles per molecule

Question 8

osmolarity of fluids in the human body

Answer 8

280 - 296 mOsM/L

Question 9

Osmolarity vs Tonicity

Answer 9

osmolarity doesnt provide information about how particles behave (their nature) or what happens to a cell in solution but it does provide units of measurement.
Tonicity predicts the movement of the molecules across the membrane by predicting nature of solutes in solution to the cell. Tonicity describes what happens to cell volume in solution but tonicity has NO units of measurement is a comparative term ONLY

Question 10

Tonicity

Answer 10

specifically depends on the concentration of non penetrating solutes e.g. NaCl

Question 11

penetrating solutes

Answer 11

will leave cell by diffusion with no movement of water because water is not needed to make up the conc of solutes in solution

Question 12

non penetrating solutes

Answer 12

water will move into the compartment that has the higher conc of non penetrating solutes

Question 13

hypertonic solution

Answer 13

contains more non penetrating solutes than cell

Question 14

hypotonic solution

Answer 14

contains less non penetrating solutes than cell

Question 15

hyper osmotic volume contraction

Answer 15

diabetes insipidus or sweating/fever

free water loss from the body due to ADH malfunction

Question 16

hypo osmotic volume contraction

Answer 16

adrenal insufficiency and aldosterone decrease

sodium is lost from the body

Question 17

iso osmotic volume contraction

Answer 17

diarrhoea or burn

fluid loss = solute loss

Question 18

hyper-osmotic volume expansion

Answer 18

eating salt

Question 19

hypo osmotic volume expansion

Answer 19

drinking deionised water

Question 20

isotonic osmotic volume expansion

Answer 20

solution of equal osmolarity added