lipids

Question 1

what do lipids contain

Answer 1

carbon, hydrogen, oxygen

Question 2

are lipids polar or non-polar

Answer 2

non-polar

Question 3

what are the functions of lipids

Answer 3

• energy source and storage- 1g of fat provides twice as much energy as carbs
• protection- protect vital organs from physical damage
• oxidation of triglycerides- produce metabolic water (camels)
• membranes- phospholipids are important component of all biological molecules
• waterproofing- leaves waxy cuticle to prevent water loss
• insulating- retain body heat, also provides electrical insulation around long nerve cells
• hormones- some hormones are lipids

Question 4

what are lipids stored in

Answer 4

adipose cells in fat stores

Question 5

what is a saturated fat

Answer 5

carbon atoms are joined by single bonds in the hydrocarbon chain

Question 6

whats the structure of saturated fats

Answer 6

straight chains

Question 7

why is the structure of a saturated fat good

Answer 7

the straight chains allow them to be packed more tightly so can store energy in a compact from
high melting point

Question 8

what is an unsaturated fat

Answer 8

carbon double bonds in the hydrocarbon chain

Question 9

what is the structure of unsaturated fats

Answer 9

from bent chains

Question 10

what is more than one unsaturated fat called

Answer 10

poly-unsaturated

Question 11

what is a triglyceride made up of

Answer 11

glycerol and three fatty acids

Question 12

what is the function of triglycerides

Answer 12

insulation and protection

Question 13

why is triglycerides more efficient than carbs

Answer 13

more C-H bonds

Question 14

what are fatty acids

Answer 14

long molecules with polar, hydrophilic end and a non-polar hydrophobic tail

Question 15

how do triglycerides from

Answer 15

condensation reaction
water is removed and an ester bond is formed

Question 16

what is a phospholipid

Answer 16

glycerol, 2 fatty acid chains and a phosphate group

Question 17

what are the main components in a phospholipid

Answer 17

hydrophilic head- negatively charge phosphate group
hydrophobic tails- non polar fatty acids

Question 18

what is a micelle

Answer 18

droplet spheres with the hydrophilic heads facing the water and the hydrophobic tails facing each other

Question 19

what is a double layered phospholipid bilayer

Answer 19

traps a compartment of water in the middle seperated from the external water by the hydrophobic sphere
- liposome

Question 20

what is the structure of cholesterol

Answer 20

a hydrocarbon tail, a central sterol nucleus made of 4 hydrocarbon rings and a hydroxyl group

Question 21

what is the function of cholesterol

Answer 21

regulate the fluidity of the membranes and strength

Question 22

what hormones are made from cholesterol

Answer 22

testosterone, oestrogen, vitamin D

Question 23

what is a glycolipid

Answer 23

combination of carbohydrate and lipid

Question 24

what is a lipoprotein

Answer 24

combination of lipids and proteins

Question 25

whats the function of lipoproteins

Answer 25

transport lipids in the blood

Question 26

what is LDL

Answer 26

low density lipoproteins

Question 27

function of LDL

Answer 27

delivers fat around the body
delivers fat to endothelial cells of arteries where its deposited as atheroma

Question 28

how is LDL production increased

Answer 28

diet high in saturated fats

Question 29

what is HDL

Answer 29

high denisty lipoproteins

Question 30

what is the function of HDL

Answer 30

removes cholestrol from blood

Question 31

why is HDL production high

Answer 31

in a diet high in unsaturated fats

Question 32

how is rate of atherosclerosis reduced

Answer 32

HDL scavenges for excess LDL and returns to liver