8. Be familiar with coenzymes common in metabolism & what they carry: NAD+, FAD,

Question

8. Be familiar with coenzymes common in metabolism & what they carry: NAD+, FAD, CoA, NADP 9. Understand what is meant by energy charge of the cell. Some Possible Short-Answer Questions (not limited to this list, however): A mutant form of the enzyme chymotrypsin has been obtained which has valine substituted for the usual serine at position 195. What effect would this substitution have on the catalytic activity of chymotrypsin? Explain in terms of the normal catalytic mechanism of chymotrypsin. Be sure to define the catalytic triad in normal chymotrypsin. 1. List 3 molecules whose binding to hemoglobin affects the binding affinity for oxygen and explain the effect on oxygen binding affinity. 2. 3, Sketch and explain the signaling cascade initiated by epinephrine binding the -adrenergic receptor. Sketch and explain the signaling cascade initiated by EGF binding the EGF receptor. How might ras be mutated in some cancer cells? 4. 5. Cell membranes are both fluid & asymmetrical. Discuss 2 examples of asymmetry found in mammalian cell membranes. Explain properties that promote fluidity of cell membranes.

Explanation / Answer

1) NAD+ - It is a coenzyme that acts as an oxidizing agent of Nicotinamide adenine dinucleotide (NAD). NAD+ accepts electrons from other molecules and becomes reduced to NADH. NADH acts as a reducing agent to donate electrons.

FAD - Flavin adenine dinucleotide (FAD) is a fully oxidized form. It accepts two electrons and two protons to form FADH2. Reduction of FAD or oxidation of FADH2 by accepting or donating one electron and one proton can form FADH.

CoA - Coenzyme A acts as a acyl group carrier in fatty acid synthesis. It helps in transferring fatty acids from the cytoplasm to mitochondria. When a coenzyme A carries an acetyl group it is callled as acetyl-CoA. When CoA is not bound to an acyl group, it is called as CoASH or HSCoA. Acetyl- CoA is obtained from glycolysis, amino acid metabolism, and fatty acid beta oxidation and is the primary input in the citric acid cycle.

NADP+ - Nicotinamide adenine dinucleotide phosphate (NADP+) is the reduced form of NADPH. It is similar to the NAD+, but the phosphate group on the 2' position of the ribose ring carries the adenine moiety. It is a cofactor used in lipid and nucleic acid synthesis.

Related Questions

Navigate

• Browse (All)
• Browse 8
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.