bio unit 5 applied science

Question 1

phospholipids

Answer 1

main component of plasma membrane

Question 2

hydrophilic

Answer 2

attracted to water

Question 3

hydrophobic

Answer 3

repelled by water

Question 4

lipid soluble substances

Answer 4

move through the membrane via the phospholipid bilayer

Question 5

protein channels

Answer 5

allow water soluble ions to diffuse across membrane

Question 6

carrier proteins

Answer 6

bind to molecules then change shape to move them across membrane

Question 7

cholesterol

Answer 7

adds strength to the membrane

Question 8

glycolipids

Answer 8

act as cell surface receptors

Question 9

glycoproteins

Answer 9

act as cell surface receptors e.g. for hormones

Question 10

fluid mosaic model

Answer 10

arrangement of proteins and phospholipid molecules in the membrane

Question 11

diffusion

Answer 11

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

Question 12

facilitated diffusion

Answer 12

the diffusion of molecules through protein channels or carrier proteins

Question 13

osmosis

Answer 13

the movement of water from higher water potential to lower water potential through a selectively permeable membrane

Question 14

solute

Answer 14

a substance dissolved in a solvent

Question 15

haemolysis

Answer 15

if red blood cells are placed in pure water this will happen

Question 16

isotonic

Answer 16

two solutions with an equal water potential

Question 17

plasmolysis

Answer 17

if a plant cell is placed in a hypertonic solution this will happen

Question 18

active transport

Answer 18

movement of molecules from low to high concentration, requires ATP

Question 19

co-transport

Answer 19

mechanism by which glucose is absorbed from the small intestine

Question 20

indirect active transport

Answer 20

using a sodium ion concentration gradient rather than ATP directly to power the movement of glucose