State the Correct Answer for Following Transketolase Enzyme Flashcards

Transketolase is an enzyme that catalyzes:
a. transfer of three-carbon units from a ketose to an aldose b. transfer of ketoses into aldoses c. transfer of xylulose-5-phosphate into ribulose-5-phosphate d. TPP-dependent transfer of 2-carbon units to the recipient aldose e. transfer of keto groups from C-2 to C-3

Which of the following reactions is catalyzed by a transketolase in the pentose phosphate pathway? I. fructose-6-P + glyceraldehyde-3-P à xylulose-5-P + erythrose-4-P II. erythrose-4-P + fructose-6-P à sedoheptulose-7-P + glyceraldehyde-3-P III. sedoheptulose-7-P + glyceraldehyde-3-P à ribose-5-P + xylulose-5-P a. I only b. II and III c. II only d. I and III e. I and II

The transaldolase catalyzed activity is similar to what glycolytic enzyme? a. phosphoglucomutase b. enolase c. glyceraldehyde-3-phosphate dehydrogenase d. PFK-1 e. aldolase

When a cell with the pentose phosphate pathway has need for more pentose phosphates, but no additional NADPH:
a. glucose-6-phosphate dehydrogenase is activated b. the oxidative and no=oxidate enzymes of the petose phosphate pathway are active c. the non-oxidative enzymes produce pentose phosphates form fructose-6-phosphate and glyceraldehyde-3-phosphate d. all enzymes of glycolysis and pentose phosphate pathway are active e. none

The primary stoarage form of lipid is ___ and it is normally stored in the ____. a. phospholipid; liver b. cholesterol; muscles c. monoacylglycerol; adipocytes d. triacylglycerols; adipocytes e. tracylglycerols; liver

The sequence for activation of the release of fatty acids from adipose cells: A. protein kinase activation B. camp production C. triacylgylcerol lipase activationD. hormone binding receptor E. adenylyl cyclase activation F. diacyglycerol lipase and monoacylglycerol lipase activity

Fatty acids are mobilized from adipose cells in response to all of the hormones EXCEPT: a. ACTH b. glucagon c. insulin d. epinephrine e. all

Bile salts are important in the initial digestion of triacylgylcerols in the intestine because they: a. are coenzymes for pancreatic lipases b. convert the inactive lipase into the active form c. emulsify the triacylglycerol globules to produce greater surface area which will increase the activity of the lipase d. activate the cleavage at the C-2 position e. permit greater permeability of the triacylglycerols through the intestinal memrane

The majority of lipid digestion occurs in the duodenum by the enzyme _____ that produces ____ and _____ for absorption. a. acid lipase; diacylglycerols; fatty acids b. triacylglycerol lipase; fatty acids; glycerol c. triacylglycerol lipase; fatty acids; glycerol d. pancreatic lipase; monoacylgylcerols; fatty acids e. pancreatic lipase; glycerol; fatty acids

Absorbed lipids are condensed with glycerol in the epithelial cells into ____ and re-packaged into _____ that are initially transported by the ____ system. a. phospholipids; VLDL; lymphatic b. triacylglycerols; VLDL; portal c. triacylglycerols; chylomicron; portal d. triacylglycerols; chylomicron; lymphatic e. triacylglycerols; VLDL; lymphatic

Chylomicrons: a. a formed in adipose tissue b. are primary energy sources for the brain c. transport dietary triacylglycerols through the bloodstream d. are formed in and secreted by the liver e. contain more phospholipid than triacylglycerol molecules

Where in the cell are fatty acids condensed with coenzyme A to form acyl-CoA for beta-oxidation? a. mitochondrial matrix b. cytoplasm c. outer mitochondrial membrane d. inner mitochondrial membrane e. none

__ carries long chain fatty acyl groups across the ____ membrane. a. biotin; intestinal b. carnitinel plasma c. CoA-SH; plasma d. carnitine; inner mitochondrial e. TPP; outer mitochondrial

The correct sequence for transport of fatty acyl groups from the cytosol to the matrix is” A. carnitine acytransferase I B. translocase of carnitine and O-acyl carnitine C. carnitine acyltransferase II D. fatty acyl-CoA synthesis E. O-acylcarnitine F. oops

The first 3 rxns of beta-oxidation of saturated FAs are analogous to which sequence of metabolic rxns already discussed? a. succinateàfumarateàmalateàoxaoloacetate b. isocitrateàalpha-ketoglutarateàsuccinateàfumarate c. OAAàcitrateàisocitrateàalpha-keto d. phosphoenolpyruvateàPiàacetyl-Coaàcitrate e. alpha-ketoà succinyl coAàsuccinateàfumarate