winter midterm Flashcards
glycosidic bond and composition of:
- maltose
- lactose
- sucrose
- alpha 1-4, 2 glucose
- beta 1-4, galactose + glucose
- alpha1-beta2, fructose + glucose
which of the enzymes is incorrectly paired with its location of function?
isocitrate dehydrogenase and glyoxosome
what does glucagon upregulate?
glycogen phosphorylase A
which steps of glycolosis generate ATP? (2)
1,3 bisphosphate –> 3 phosphoglycerate
phosphoenolpyruvate –> pyruvate
glycogen synthase:
requires glucose-1-P to be activated by UDP
what is correct about the citric acid cycle?
directly generates 2 water molecules/acyl-CoA
the structure shown below is:
fructose-2,6-bisphosphate
triglyceride levels of the 4 lipoproteins
chylomicrons: 85
VLDL: 50
LDL: 10
HDL: 4
which enzyme is mismatched with is function?
lipoamine - deamination
which of the following is true about ketogenesis?
ketogenesis is absent in people with systemic carnitine deficiency
omega oxidation of fatty acids:
involves sequentially alcohol, aldehyde and acid intermediates
identify the ketone bodies (structure)
CH3 - C(=O) - CH2 - C (=O,O-) and
CH3 - C(H,OH) - CH2 - C (=O, O-)
what is thiolase involved in? (4)
- ketogenesis pathway
- works in mitochondria
- converts acetoacetyl-CoA back into Acetyl-CoA in the peripheral tissues
- aka ACAT
what phospho/sphingolipids are found primarily in the outer leaflet of the plasma membrane?
phosphotidylcholine and sphingomyelin
peroxisomal B-oxidation of fatty acids involves:
- export of NADH and H+ to the mitochondria for reoxidation to NAD
- export of acetyl CoA to mitochondria to enter the CAC
lioprotein lipase action involves:
activation of the enzyme by alipoprotein CII
pyruvate kinase remains active in muscle during glycogenolysis because:
- muscle need glycolysis to generate energy
- muscle lacks glycogen receptors
- muscle lacks glucose-6-phosphatase
PFK-1 is downregulated by:
ATP and citrate
which of the following enzymes/pathways is correctly listed with its regualtor?
all of the above
Fehlings solution?
- reducing sugars (glucose, galactose, fructose) interact with the solution to produce a red colour (specifically interact with the Cu ions)
- non-reducing sugars dont interact (sucrose) so theres no color change
steps of mitochondrial B-oxidation of fatty acids to acetyl CoA:
occur while fatty acids are attached to coenzyme A
pyruvate dehydrogenase:
- occurs in mitochondrial matrix
- converts pyruvate to acetyl CoA
- eliminates Co2/generates NADH (coupled)
- has 3 subunits and 5 coenzymes (TPP, lipoic acid, coenzyme A, FAD, NAD+)
human G6PD deficiency results in:
- compromised NADPH production for antioxidant defences
- little biosynthesis of ribose-5-phosphate
- increased sensitivity to chemotherpeutic drugs
which of the following statements about the synthesis of DHA from an essential acid in mamals is (are) correct?
all of the above
during later stages of fasting, the brain becomes dependent on which of the following enzymes to efficiently generate energy?
thiolase, pep carboxykinase, 3B-ketoacyl CoA transferase
everything but citrate
