biological molecules: lipids

Question 1

are lipids non polar or polar, insoluble or solube

Answer 1

non polar
insoluble

Question 2

what is a triglyceride made of

Answer 2

1 glycerol
3 fatty acids - carboxylic acids

Question 3

what is the bond and reaction from triglycerides called

Answer 3

esster bond and esterification
another condensation reaction making 3 water molecules

Question 4

what is a saturated fatty acid

Answer 4

no double bonds

Question 5

what is an unsaturated fatty acid

Answer 5

double bonds
1 double bond - monounsaturated
2+ double bonds - polyunsaturated

Question 6

what does the prescence of double bonds mean

Answer 6

molecule kinds/bends
so they cannot fold together closely
means liquid at room temperature and more described as oils

Question 7

what are phospholipids and are they soluble

Answer 7

modified triglycerides
soluble

Question 8

phospholipid structure

Answer 8

hydrophobic tails - nonpolar
hydrophilic head - charged

Question 9

phospholipids - surface active agents

Answer 9

form a layer on teh surface of the water
phosphate heads in the water and the fatty acids tails sticking out

Question 10

phospholipids - cell membranes

Answer 10

they seperate an aqueous enviroment from ells which exist from the aqueous cytosol within cells

Question 11

cholesterol

Answer 11

a sterol
liver and intestines
important role in cell membrane formation
adds stability to cell membranes and regulates their fluidity be keeping them fluid at low temps and stops them being too fluid at high temps
vitamin D bile

Question 12

roles of lipids

Answer 12

membrane formation
hormone production
electrical insulation
waterproofing

Question 13

under skin adn near vital organs roles of lipids

Answer 13

thermal insulaltion to reduce heat loss eg penguins
cushioning to protect vital organs eg heart
buoyancy for aquatic animals like whales

Question 14

lipid tests

Answer 14

emulsion test
sample mixed with ethanol - resulting solution is mixed with water and shaken
if white emulsion is formed on top of solution it indicates a presence of lipid
if clear its negative

Question 15

cholesterol probems - gallstones

Answer 15

cholesterol is used to make bile which is stored in the gall bladder
if there is excessive cholesterol this can lead to the formation of gallstones which can block the bile duct

Question 16

cholesterol problems - athersclerosis

Answer 16

cholesterol can be deposited in the inner linings of blood vessels which can lead tp the ndition athersclerosis in which clots may form inside the blood vessel
if its in a blood vessel supplying the heart it could result in a heart attack