Anomers can be interconverted.... -by an isotopic exchange reaction -by rotation about carbon-carbon bonds -Both A and B -Neither A nor B

--As glucose is split in the cytosol of the cell, is there a release of carbon dioxide as by-product of the reaction?

Tissues that are unable to produce nucleotides de novo depend on ____________________ to maintain an adequate supply of adenine nucleotides. (A) the redox reactions carried out by ribonucleotide reductase (B) the action of PRPP amidotransferase(C) uptake of ATP through dietary intake(D) salvaging hypoxanthine using HGPRT (E) the action of xanthine oxidase

Which of the following best describes the use of 2-deoxyglucose in allowing for cancer therapy? Elevates p53 levels directly to regulate glycolytic flux Blocks activation of HIF1transcriptional activation Diminishes lactate production by inhibiting lactate dehydrogenase to allow increased levels of pyruvate to force the transport of pyruvate into the matrix and the function of the TCA cycle Diminishes lactate export from the cell to allow increased levels of pyruvate to force the transport of pyruvate into the matrix and the function of the TCA cycle Competes with glucose for hexokinase, allowing inhibition of glycolytic flux, reducing ATP production.

14CO2 was bubbled through a suspension of liver cells that was undergoinggluconeogenesis from lactate to glucose. Which carbons in the glucose molecule would become radioactive?

Also, briefly describe what happens in this scenario to: -Glucose - Glucose - Glycogen - Protein/Amino acids - Triglycerides

2. Phospholipases (PL) are enzymes that hydrolyzes PLA1 phospholipids into fatty acids and other lipophilic substances. Different class of phospholipase cleaves different bond in a phospholipid molecule. Shown on the right are the cleavage sites of four classes of PL: PLA1, PLA2, PLC, and PLD. R1 R2 -O-P-'·O-R3 (a) Write down the reaction of phosphatidylcholine (PC) cleaved by PLA2. Suppose the two acyl groups are R1 and R2 as shown in the figure. Make sure the chiral carbons in the reactions have the right stereochemistry (i.e., use wedge-dash notation), and the charges on the atoms reflect the molecule in neutral pH. PLA2 PLC PLD (b) Which PL is needed in order to release choline for salvage? (c) What is the structure and name of the remaining molecule after cleaving PC by the PL in (b) and releasing choline. No need to use wedge-dash notation. (d) The molecule in (c) can be used to synthesize triacylglycerol. Write down the reactions, including the enzymes and cofactors. Assume the…

1. Pepsinogen (an inactive form of the enzyme) that forms in the main cells of the stomach has a molecular weight of 42,000 D. In the gastric juice, the pepsinogen turns into the active enzyme pepsin, while its molecular weight decreases to 35,000 D. Explain the mechanism of regulation of enzyme activity. To do this: a) draw a scheme for regulating the activation of pepsin; b) name the class of the enzyme that converts pepsinogen to pepsin; c) indicate which levels of protein structural organization change when pepsin is activated.

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Write a pathway leading from glucose to lactose in mammary gland, and write a balanced equation for the overall pathway.