Membranes

Question 1

Membranes

Answer 1

control the exchange of materials between the cell and its environments,
receives messages from chemicals like hormones,
flexible so can break and fuse easily
allow cellular compartments to have different conditions (pH)

Question 2

Glycerol

Answer 2

H
                           -
                    H - C - H  
                          -   
                    H - C - H  
                           -
                    H - C - H 
                           -
                          H

Question 3

Fatty Acid

Answer 3

Hydrocarbons with a =O and -OH

   R-C=O
       --
       OH

Question 4

Saturated

Answer 4

Contains NO carbon to carbon double bonds

       C-C-C-C-C-C=O
                           --
                          OH

Question 5

Unsaturated

Answer 5

Contains carbon to carbon double bonds

    C-C=C-C-C-C=O
                           --
                          OH

Question 6

Phosphate Group

Answer 6

PO4’2

                                O"
                                 -
                           O=P-O
                                 -
                                O'

Question 7

Phospholipid

Answer 7

Phosphate Group
Phosphoester Bond
Glycerol
Ester Bonds
Fatty Acids

Question 8

Hydrophobic

Answer 8

water hating

Question 9

Hydrophilic

Answer 9

water loving

Question 10

Micelles

Answer 10

phospholipids form micelles when submerged in water

Question 11

Phospholipid bilayer

Answer 11

membranes are formed from a phospholipid bilayer
heads point out 
-towards the aqueous solution
tails point in
-away from the aqueous solution

Question 12

Phospholipids……….

Answer 12

allow lipid soluble substances to enter easily,
prevent water soluble substances entering,
make the membrane flexible and self sealing,

Question 13

Fluid Mosaic

Answer 13

the proteins can move freely through the lipid bilayer

contains saturated and unsaturated fatty acids

Question 14

what can diffuse through the bilayer

Answer 14

fat-soluble molecules can diffuse through

the bilayer

Question 15

what can not diffuse through the bilayer

Answer 15

polar molecules require a protein to diffuse through the bilayer

Question 16

how can polar molecules pass through the bilayer

Answer 16

carrier and channel proteins form channels through the bilayer

Question 17

Peripheral Proteins

Answer 17

function as enzymes on one membrane surface 
or give mechanical support

Question 18

Glycoprotein

Answer 18

Proteins which have carbohydrate chains attached

Question 19

Glycolipids

Answer 19

Lipids with a carbohydrate chain attached

Question 20

Channel proteins

Answer 20

work by simple or facilitated diffusion

Question 21

Carrier proteins

Answer 21

require energy therefore work by active transport

Question 22

Cholesterol

Answer 22

adds strength 
very hydrophobic,
limits movement 
less fluid at high temperatures,
prevents leakage of water and polar substances from the cell,

Question 23

Substances that go into the cell

Answer 23

oxygen
glucose
amino acids
water

Question 24

Substances that exit the cell

Answer 24

carbon dioxide
urea
water

Question 25

Phosphate Group

Answer 25

• hydrophilic head

- polar

Question 26

Glycerol

Answer 26

• Hydrophobic

- non polar

Question 27

Fatty Acids

Answer 27

• Hydrophobic tail

- non polar