lipid metabolism

Question 1

structure of fats

Answer 1

glycerol + fatty acids

unsaturated if double bonds

Question 2

solubility

Answer 2

• methyl group and carbon chain is fat soluable but water insoluable
• carboxylgroup is water soluable, but fat insoluable

Question 3

omega 3

omega 6

Answer 3

3- alpha linolenic acid

6- linoleic acid

Question 4

conjugated fatty acids

Answer 4

• polyunsaturated fatty acids¨

- at least one pair of double bonds are separated by only one single bond

Question 5

trans fatty acids

Answer 5

• adverse effect: bad ldl and cholesterol increase

- straight molecule with double bond

Question 6

role of bile salts

Answer 6

• emulsify the dietary lipids

- bile salts are produced in liver and secreted from gall bladder

Question 7

pancreatic lipases

Answer 7

• degrades emulsified fats
• secreted into intestine from pancreas
• generate free fatty acids and mono and diglycerols

Question 8

what does lipase create

Answer 8

• 1,2-diacylglycerol
• 2-acylglycerol
• phospholipids are degraded releasing free fa and lysophospholipid

Question 9

what happens after absorption of lipase products by intestinal wall

Answer 9

• resynthesis of triacylglycerols

Question 10

what happen to triacyl glycerols

Answer 10

• solubalized in lipoprotein complexes calle dchylomicrons

Question 11

what is a chylomicron

Answer 11

contain lipid droplets suroounded by polar lipids and a protein layer

Question 12

triacyl glycerols synthesized in liver

Answer 12

packaged into VLDL and released directly to blood

Question 13

chylomicron release

Answer 13

released into blood via lymph system

Question 14

triacyl glycerol in VLDL and chylomicrons

Answer 14

• hydrolyzed into free fatty acid and glycerol in capillaries of adipose tissue and skeletal muscle

Question 15

what happen to glyerol after absorption of cells

Answer 15

returned via blood to liver

- converted to DHAP

Question 16

carnithine shuffle

Answer 16

before beta oxidation fatty acids enter mitochonrial matrix with carnithine by facilitated diffusion

Question 17

energy gain from beta oxidation

Answer 17

• 8 acetyl coa will enter citric acid cycle

- NADH and FADH2 will enter respiratory chain

Question 18

phosphoglycerides

Answer 18

• phosphatidic acid
• lechitin
• cephalin
• inositol phosphatides
• plasmalogens

Question 19

main role of phosphoglycerides

Answer 19

• membrane constituents

Question 20

geeral structure of phosphoglycerides

Answer 20

• aminoalcohol
  
  • cholamine, choline
• glycerol+FA+P

Question 21

lechitin

Answer 21

• most common phospholipid
• emulsifier: polar and non polar properties
• component in lipid bilayer of cell membrane
• contain choline: N group is +

Question 22

cephalin

Answer 22

• =ethanolamine
• found in most cell membranes, brain tissue
• important in blood clotting process

Question 23

inositolphosphatides

Answer 23

• membrane constituents

- 2nd messenger function

Question 24

pklasmalogens

Answer 24

1 or 2 ether bonds btw glycerol and FA

- platelet activating factor

Question 25

sphingolipids

Answer 25

- sphingomyelin - cerebrosid - gangliosid

Question 26

main role of sphingolipids

Answer 26

membrane constituent | - in nerve and brain tissue

Question 27

sphngosine

Answer 27

- main constituent of sphingolipids - 3 parts: - 3 C chain with two alcohols - amine - long hydrocarbon chain

Question 28

sphingomyelin

Answer 28

- nerve cell membranes

Question 29

cerebrosides

Answer 29

- glucocerebrosid - single sugar group - galactocerebrosides - neuronal cell membrane - glucocerebrosides

Question 30

gangliosides

Answer 30

- contain more than one carb | - give identity of cell

Question 31

steroids

Answer 31

- sterols - zoosterols: cholesterol - phytosterol: stigmasterol - mycosterol: ergosterol

Question 32

cholesterol

Answer 32

- cholesterol bound to lipid membrane makes it less fluid and stonger

Question 33

role and metabolism of cholesterol

Answer 33

- syntheis in liver, gonades, intestine - stored esterified by palmitic or linoleic acid - bile salts and steroid hormnes will be synthesized from it

Question 34

bile acids

Answer 34

- primary bile acids produced in liver and collected in gall bladder, form bile salts