Passive membrane transport

Question 1

cells are bound by

Answer 1

Semipermeable membrane

Question 2

Cell has organelles that are bound by a

Answer 2

membrane, to allow substances move inside or outside the cell

Question 3

cells are continuously bathed in an ECF called

Answer 3

interstitial fluid

Question 4

interstitial fluids ingredients:

Answer 4

amino acids, sugars, fatty acids, vitamins, regulatory substances, salts, and waste products

Question 5

substances that move without energy are

Answer 5

passive

Question 6

cell provides metabolic energy to move substances across the membrane

Answer 6

active

Question 7

define diffusion:

Answer 7

the tendency of molecules or ions to scatter evenly throughout the environment

Question 8

molecule diffuse either

Answer 8

along or down their concentration gradient

Question 9

overtime in a closed container, diffusion will produce

Answer 9

uniform mixture (equilibrium)

Question 10

molecules will diffuse passively through the plasma if they are

Answer 10

1) lipid-soluble
2) small enough to pass through membrane channels
3) assisted by carrier molecules

Question 11

distribution of molecules is always from

Answer 11

high concentration to low concentration

Question 12

non polar and lipid soluble substances diffuse

Answer 12

directly to the bilayer

Question 13

examples of non polar and lipid soluble substances:

Answer 13

O2
CO2
ALCHOHOL
FAT SOLUBLE SUBSTANCES

Question 14

Polar and charged particles can diffuse through membrane if:

Answer 14

they are small enough to pass through the water pilled pores constructed by the channel proteins (aquaporin)

Question 15

facilitated diffusion

Answer 15

molecules that are too polar to dissolve in the lipid bilayer and too large to pass through membrane proteins. they combine carrier molecules in the plasma membrane and are released into the cytoplasm

Question 16

carrier-mediated transport is limited by

Answer 16

the number of receptors present

Question 17

osmosis

Answer 17

diffusion of water through selectively permeable membrane

Question 18

when does osmosis occur

Answer 18

when the water concentration differs on the two sides of the membrane

Question 19

influence of membrane permeability on diffusion and osmosis

Answer 19

1) membrane is permeable to both water and solute molecules. solute moves along its own concentration gradient in the opposite direction; when it comes to equilibrium, the solutes have the same osmolarity and volume
2) similar to “1” except that the membrane is impermeable to the solute. water moves by osmosis from the left to the right compartment until the concentration on both sides are identical

Question 20

Tonicity

Answer 20

The ability of an extracellular solution to make water move into or out of a cell by osmosis

Question 21

tonicity effect on RBC (isotonic solutions, hypertonic solutions, and hypotonic solutions)

Answer 21

• Isotonic solutions: same concentration in and out of the cell (normal size and shape)
• Hypertonic solutions: more solutes inside the cell (shrunk and water is lost)
• Hypotonic solutions: fewer solutes inside the cell (cell take in water by osmosis until they bloat and burst)

Question 22

filtration in passive processes

Answer 22

passive transport process that forces water and solutes through a membrane or capillary wall by fluid or hydrostatic pressure

Question 23

what is a hydrostatic pressure

Answer 23

the pressure that has the ability to move fluid outside the capillaries into the interstitial space

albumins and other proteins inside the capillaries create osmotic force to hold the water inside the cells

Question 24

examples of passive transport

Answer 24

• simple diffusion: movement of small or lipophilic molecules (O2, CO2 etc)
• osmosis: movement of water molecules depending on the solute concentration
• facilitated diffusion: movements of large or charged molecules through membrane proteins (ions, glucose, sucrose etc)