Chapter 7

Question 1

lipid bilayer structure

Answer 1

polar surfaces, non-polar interior

Question 2

what can pass through the membrane?

Answer 2

small non-polar substances, all other need channel/carrier/transport

Question 3

diffusion

Answer 3

particles move from area of high concentration to low concentration (naturally occurring)

Question 4

passive diffusion

Answer 4

particles pass through membrane, flowing with concentration gradient (high to low concentration)

Question 5

facilitated diffusion

Answer 5

particles too large or too polar/charged to pass through membrane, will pass through channels or protein carriers, flow with concentration

Question 6

active transport

Answer 6

particles flow against gradient, from low to high concentration, requires pump proteins that use energy

Question 7

primary active transport

Answer 7

uses ATP

Question 8

secondary active transport

Answer 8

transport one particle with gradient and that provides energy to transport another particle against its gradient

Question 9

cotransport

Answer 9

transport of 2 different solutes by one carrier (sometimes same direction but one with gradient and one against)

Question 10

membrane potential

Answer 10

created by distribution of charges on either side of a membrane, usually negative cytosol and positive outside (H+ help maintain membrane potential)

Question 11

large molecules

Answer 11

pass through membrane by exocytosis or endocytosis, packaged inside membrane vesicles

Question 12

receptor-mediated endocytosis

Answer 12

uses membrane receptor protein to bind specific molecules to bring them in (how cholesterol gets into cells)

Question 13

exocytosis

Answer 13

transports proteins through endomembrane system, ER to golgi to plasma membrane, proteins are packaged inside membrane vesicles for each individual step, inside to outside, carries specific proteins/collagen

Question 14

endocytosis

Answer 14

receptors bind causing it to reshape and form vesicle, large to small