Biochemistry Quiz #02

If there is a specific chain composed of 15 glucosyl residues (from the non reducing end to the branch point), and it started to be degraded (by the specialized enzymes) from the non-reducing end until removal the branch. The number of glucose monomer expected to be released from the chain:

If FADH2 enters ETC, at the end we have about 48 kilojoules of energy calculate the loss energy. (it requires 7 kilojoules to phosphorylate 1ATP)

One of the early steps in glycogenesis is formation of UDP-glucose from glucose-1-phosphate and UTP according to the reaction:

Glucose-1-phosphate + UTP → UDP-glucose + PPi

One would expect this reaction to occur spontaneously if ΔG° were large and negative, but in fact, ΔG° for this reaction is nearly zero. What, then, drives the reaction?

Hydrolysis of ATP, forming phosphate, ribose and adenine

Hydrolysis of UTP

Presence of glycogen synthase, a ubiquitous enzyme

Presence of the ubiquitous enzyme pyrophosphatase, which rapidly hydrolyzes pyrophosphate

Liver glycogen contributes to the maintenance of glucose but not muscle glycogen. Which of the following enzyme is absent in muscle?

Glycogen phosphorylase

Hexokinase

Glucose-6-phosphatase

Debranching enzyme