lipids 2- phospholipids and cholestrol

Question 1

describe structure of phospholipids

Answer 1

have the same structure as triglycerides.

only two fatty acids, as one is replaced by a phosphate group

1 glycerol
2 fatty acids
phosphate group

Question 2

how do phospholipids act in water

Answer 2

phosphate group is polar .

fatty acids are non polar and repelled by water

HEAD- hydrophilic
TAIL- hydrophobic

Question 3

what does amphipathic mean and what molecule is amphipathic

Answer 3

has both hydrophobic and hydrophilic parts

Question 4

what molecules of the phospholipid are present in the tail and the head

Answer 4

tail- Fatty acids, non polar and hydrophobic

head- phosphate and glycerol which are polar, hydrophilic

Question 5

what does hydrophobic mean

Answer 5

repelled by water

Question 6

what is a micelle

Answer 6

a structure formed by phospholipids, where tails are pointed inside, and heads pointed outwards in water. creating a spherical structure

Question 7

the phospholipid bilayer is selectively permeable, what does it mean

Answer 7

small
non polar
molecules move through tails in bilayer.
membrane can control what goes in and out of the cell.

Question 8

what is cholestrol

Answer 8

a steroid alcohol

type of lipid

Question 9

what is the strucutre of cholestrol

Answer 9

doesnt consist of glycerol or fatty acids

carbon rings.

Question 11

is cholestrol hydrophobic or hydrophilic

Answer 11

hydrophobic

Question 12

what is the role of cholestrol in the phospholipid bilayer

Answer 12

can sit in the middle of the phospholipid bilayer