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Some anaerobic prokaryotes use nitrate $\left({\mathrm{NO}}_3^{-}\right)$as the terminal electron acceptor for energy metabolism. Assuming 100%efficiency, how much ATP could be synthesized by the oxidation of NADH by nitrate?

How many stereoisomers are possible for (a) a ketopentose, (b) a ketohexose, and (c) a ketoheptose?

Draw the furanose and pyranose forms of D-ribose.

Some bacteria produce thiosugars, which contain a C—S covalent bond, such as 2-deoxy-2-thio-β-D-glucose. Draw the structure of this sugar.

Which of the 10 reactions of glycolysis are (a) phosphorylations, (b) isomerizations, (c) oxidation–reductions, (d) dehydrations, and (e) carbon–carbon bond cleavages?

The sucrose substitute tagatose (Fig. 8-2) is produced by hydrolyzing lactose and then chemically converting one of the two resulting aldoses to a ketose. Which residue of lactose gives rise to tagatose?

Compare and contrast the structures and functions of cellulose, chitin, starch, and glycogen.

A growth factor that acts through a receptor tyrosine kinase stimulates cell division. Predict the effect of a viral protein that inhibits the corresponding protein tyrosine phosphatase.

Nearly all enzymes that require a nicotinamide cofactor use either $NA{D}^{+}/NADH$ or $NAD{P}^{+}/NADPH$ (Figure $11-3$) but not both. Compare the net charge of each cofactor.

What type of sugar derivative is rhamnose?