cell membrane and transport

Question 1

who made the fluid mosiac model

Answer 1

singer and nicholson

Question 2

describe a phospholipid bilayer

Answer 2

phosphate head is hydrophilic and goes by water where the fatty acid tails turn in as they are hydrophobic

Question 3

what is diffusion

Answer 3

movement of molecules or ions from a high concentration gradient to low.

Question 4

what are factors of diffusion

Answer 4

concentration gradient, distance of travel, SA of membrane, thickness of membrane, increase in temperature

Question 5

what is facilitated diffusion

Answer 5

use of protein carriers, requires ATP

Question 6

factors of facilitated diffusion

Answer 6

respiratory inhibitor, number of protein carriers

Question 7

what is co transport

Answer 7

brings molecules and ions into cell together on the same protein carrier- ATP

Question 8

what is active transport

Answer 8

uses ATP, goes against concentration gradient, low to high conc gradient using protein carrier

Question 9

factors of active transport

Answer 9

respiratory inhibitor (cyanide)

Question 10

what is bulk transport

Answer 10

large particles enter by endocytosis. cell membrane engulfs particle forming vesicle and leaves by exocytosis

Question 11

what is the definition of osmosis

Answer 11

movement of water from high water potential through a partially permeable membrane

Question 12

definition of water potential

Answer 12

tendency of water to diffuse from one area to another

Question 13

whats the water potential formula

Answer 13

Ww = Ws + Wp

Question 14

what is the definition of a hypotonic solution

Answer 14

water potential is higher than cell. water will move into cell by osmosis

Question 15

what is the definition of a hypertonic solution

Answer 15

water potential is lower than cell. water will move out of the cell through osmosis

Question 16

what is the definition of isotonic solution

Answer 16

same water potential therefore no net movement

Question 17

what happens in an animal cell when its placed in a hypotonic solution

Answer 17

cell will swell and burst as water will enter

Question 18

what happens to a plant cell when placed in a hypotonic solution

Answer 18

vacuole swell and push against cell wall, and becomes turgid

Question 19

what happens to an animal cell when placed in a hypertonic solution

Answer 19

cell will shrink

Question 20

what happens to a plant cell when placed in a hypertonic solution

Answer 20

vacuole shrink and cell becomes plasmolyzed (membrane pulls away)

Question 21

what happens to an animal cell when placed in an isotonic solution

Answer 21

optimal medium water potential of cell is equal to water potential of solution

Question 22

what happens to plant cell when placed in an isotonic solution

Answer 22

cell becomes flaccid - incipient plasmolysis

Question 23

what can we use to test concentration in cell

Answer 23

potato cylinders and beetroot disks