Questions 36 - 42 Fat and Protein

36. Fat Digestion Which treatment would LEAST likely affect the uptake of fatty acids into the epithelial cells of the small intestine after a SINGLE fat meal? Co-consumption of a drug which prevents emptying of the gall bladder Co-consumption of a drug to prevent the formation of bile salts in the liver Substituting 50% of the fat in the meal with Olestra Co-consumption of a pancreatic lipase inhibitor with the meal Co-consumption of a compound that prevents the formation of micelles 34 65 52 39 30 would prevent efficient digestion of fat bile salts already in the gall bladder only half the fat would be available would not be able to digest the fat would not be able to emulsify the fat – lipase wont work

37. Chylomicrons Which statement BEST DESCRIBES chylomicrons? Lipoproteins that carry dietary fat to the peripheral tissues Discs of phosopholipid that mop up loose cholesterol in the blood stream Milky droplets formed from the churning of a lipid/salt mixture in the small intestine Microscopic droplets excreted by tissues that have too much cholesterol An emulsion of fat and protein in the stomach looking good! 175 13 19 3 9 a description of HDL chyme no such thing not sure that this exits

38. Fate of Dietary Fat Which statement regarding the disposal of dietary fat is CORRECT? Fat is transported around the bloodstream in micelles made from bile salts Very Low Density Lipoproteins (VLDL) transport dietary fat from the intestine to the liver Unsaturated fat goes to the liver, but saturated fat goes to the peripheral tissues Lipoproteins are taken up into cells before being acted on by lipoprotein lipase Peripheral tissues encounter dietary fat before the liver lipoproteins made from phospholipid 47 14 12 20 126 this is chylomicrons not distinguished all the hydrolysis in capillaries chylomicrons delivered via the lymph

39. LDL metabolism What would be a consequence of taking a drug that inhibited Low Density Lipoprotein (LDL) uptake? A decrease in the rate of cholesterol synthesis by the peripheral tissues. An increase in the concentration of LDL in the bloodstream Decreased intestinal absorption of cholesterol Decreased intestinal absorption of fat Prevention of bile salt synthesis 24 144 31 11 5 rate UP, no LDL-chol coming in seems obvious – genetic defect too no relevance no relevance perhaps less, liver takes up LDL?

40. Role of HDL Which statement BEST DESCRIBES the role of High Density Lipoprotein (HDL)? HDL is formed by the removal of fat from LDL HDL is assembled in the peripheral tissues and is secreted into the bloodstream HDL is assembled in the peripheral tissues and is secreted into the lymphatic circulation A high HDL:LDL ratio is positively correlated with heart disease HDL is produced by the liver and picks up cholesterol from the periphery HDL different & LDL already fat depleted 7 16 8 13 171 made in the liver – but close wrong in both ways opposite… but positively unfair really exactly

41. Essential Amino Acids Which statement is CORRECT? Essential amino acids are made into protein but non-essential amino acids are used for energy Consumption of a large amount of non-essential amino acids will not counteract insufficient consumption of essential amino acids Essential amino acids are only found in animal products Aspartate, glutamate and alanine are all essential amino acids A deficiency in one essential amino acid intake will increase the storage of the other 19 amino acids all proteins contain a mix 5 188 7 14 6 horrid double negative (sorry) – but true no – but some plant products deficient in specific essentials easy to work out that all are NON-essential a deficiency in just one aa makes ANY protein synthesis hard

42. Disposal of excess amino acids Which statement BEST DESCRIBES the fate of amino groups derived from the catabolism of amino acids in muscle? The amino groups are mainly excreted from the muscle as ammonia The amino groups are mainly excreted from the muscle as urea The amino groups become linked to pyruvate for transport to the liver The amino groups are stored on pre-existing proteins by converting glutamate residues in proteins to glutamine The amino groups are stored on pre-existing polynucleotides by converting thymine bases to cytosine most come out as alanine so no 17 76 107 12 5 urea made in liver yes, aminated pyruvate is alanine would change the protein function! similarly crazy!