block 3 lecture 8 bile and plasma lipids

Question 1

what is a phospholipid?

Answer 1

lipid based molecule with a polar head and a hydrophobic tail

Question 2

what is metabolism?

Answer 2

chemical reactions involved in maintaining an organism

Question 3

what is glycolysis?

Answer 3

glucose is converted to pyruvate

Question 4

what is gluconeogenesis?

Answer 4

conversion of pyruvate to glucos

Question 5

what is glycogenolysis?

Answer 5

glycogen is converted to glucose

Question 6

what is lipoysis?

Answer 6

conversion of lipid to free fatty acids

Question 7

what is a ketone body?

Answer 7

lipid based energy molecule

Question 8

what is cholesterol important for?

Answer 8

hormone synthesis and the lipid bilayer

Question 9

how are hydrophobic lipid molecules converted into amphipathis

Answer 9

adding phosphate groups

Question 10

what is the structure of the amphipathic lipids?

Answer 10

hydrophobic on the outside hydrophobic on the inside

Question 11

what are lipoproteins for?

Answer 11

substrates for energy metabolism
essential components for cells
precursors for hormones
lipid soluble vitamins
precursors for bile acids

Question 12

what are the two lipid transport pathways?

Answer 12

exogenous and endogenous

Question 13

what happens in the exogenous pathway?

Answer 13

take in lipid in the diet and pass into your blood stream as clarithromycins

Question 14

what happens in the endogenous pathway?

Answer 14

fats produced in the liver are altered around the body into different types of lipoprotein

Question 15

what are chylomicfrons predominantly made up of?

Answer 15

triglyceride

Question 16

what is the composition of VLDL?

Answer 16

lots of triglyceride

Question 17

where are chycomocrons synthesised?

Answer 17

small intestines

Question 18

what are chylomicrons synthesised from?

Answer 18

trigycerides, phospholipids and apoB

Question 19

where do the chylomicrons go after they have been in the small intesting?

Answer 19

released in the lymph system

Question 20

how do the chylomicrons get into the blood stream?

Answer 20

thoracic duct

Question 21

what happens to the chylomicrons in the blood?

Answer 21

metabolised by lipoprotein lipase

Question 22

what does lipoprotein lipase break down triglycerides into in the blood?

Answer 22

fatty acid and glycerol

Question 23

what happens to the chylomicron remnant in the blood

Answer 23

picked up by apoE receptors on the liver which can process it into something else

Question 24

what is the lipoprotein lipase expression linked to?

Answer 24

insulin

Question 25

what happens if there is a mutation in liporpotein lipase?

Answer 25

lots of chylomicrons

Question 26

what is liporpotein lipase bound to?

Answer 26

surface of vascular endothelial cells

Question 27

where do you find lots of chylomicrons?

Answer 27

adipose tissue/skeletal muscle/myocardium and mammary glands

Question 28

in the endogenous pathway where are VLDLs produced?

Answer 28

liver

Question 29

what are the VLDLOs in the endogenous pathway broken down into in the blood?

Answer 29

broken down into intermediate density lipoproteins

Question 30

what happens to the intermediate density lipoproteins in the endogenous pathway?

Answer 30

may return to the liver or be broken down into LDLs

Question 31

what happens to the LDLs produced from VLDLs in the endogenous pathway?

Answer 31

transported back to the liver or enter peripheral tissues

Question 32

what is high LDL associated with?

Answer 32

greater risk of CHD

Question 33

why is high LDL associated with thrombotic events?

Answer 33

can be oxidised which activates platelets

Question 34

what happens after perippheral tissue pick up LDL?

Answer 34

LDL is internalised by clathrin pits

Question 35

what happens to the clathrin pit vescile?

Answer 35

becomes declathrinated

Question 36

what does declathrination of the vescile change?

Answer 36

pH

Question 37

what does the decrease in pH in the vesicle do?

Answer 37

causes the destruction of LDLs into amino acids/fatty acids/cholesterol

Question 38

what is the route in reverse cholesterol transport?

Answer 38

peripheral tissue to the blood to the liver

Question 39

what do abnormalities in serum lipoprotein profile suggest?

Answer 39

problems in metabolism/liver function/renal function

Question 40

what contributes to levels of HDL/LDL?

Answer 40

diet/excersize/body fat/type 2 diabetes/genetics

Question 41

how does familial hypercholesterolemia present?

Answer 41

deposits under the skin

Question 42

what are patients with familial hypercholesterolemia at risk to?

Answer 42

cardiovascular disease

Question 43

what do statins do?

Answer 43

activate HMG Co A reductase | elevate HDLs

Question 44

what can hyperlipidemia be caused by?

Answer 44

hormones/metabolic disorders/renal dysfunction

Question 45

how is white adipose tissue produced?

Answer 45

glucose - glycerol - fat | VLDLs/chylomicrons broken down in the body by LPLs

Question 46

what is the breakdown of fat stores driven by?

Answer 46

adrenaline noradrenaline glucagon

Question 47

what is fat broken down into in prolonged starvation?

Answer 47

ketone bodies

Question 48

what are the two main ketone bodies?

Answer 48

acetoacetate | 3 hydroxybutrate

Question 49

when do you find high ketone bodies?

Answer 49

prolonged starvation | diabetes

Question 50

what is the difference between white and brown adipose tissue?

Answer 50

white: 1 droplet brown: lots of little droplets, mitochondria have thermogenin which produces heat

Question 51

what produces heat?

Answer 51

brown adipose tissue

Question 52

how is heamoglobin broken down?

Answer 52

haemoglobin converted to heam and globin haem converted to biliverdin biliverdin converted to bilirubin

Question 53

what happens to bilirubin?

Answer 53

protein bound to albumin in blood and is transported to the liver

Question 54

what happens to bilirubin in th liver?

Answer 54

undergoes conjugation with glucorinic acid

Question 55

why is bilirubin conjugated?

Answer 55

make it more soluble in water

Question 56

what happens to the conjugated bilirubin?

Answer 56

excreted in the bile duct to the small intestine

Question 57

what happens to the conjugated bilirubin in the intestine?

Answer 57

converted to urobilinogen and moved to the kidneys or removed in fecaes

Question 58

what might you see if someone has a liver problem?

Answer 58

jaundice