Question

NADH is required for the one-step reaction by which pyruvate is converted to;

A.	Oxaloacetate
	B.	Acetyl CoA
	C.	Phosphoenolpyruvate
	D.	Lactate

Bacterial DNA is not bound to histones unlike eukaryotic DNA T/F?

All sphingolipids have in common which of the following?

A. A glycerol backbone

B. Ceramide

C. Phosphorylcholine

D. N-acetylneuraminic acid (NANA)

E. A steroid ring structure to which spingosine is attached

Answer 1

1. The answer is D. Lactate. The process takes place in some bacteria,. Yeast and in muscle cells of animals. The process is called fermentation. It is lactic acid fermentation where pyruvate is converted to lactate. This is acheived by lactate dehydrogenase enzyme. Here the reducing agent is NADH is oxidized to NAD+. Only less than seven percent of energy is released in this process. All other process converts NAD to NADH.
2. The statement is true. Bacterial DNA lach histones instead non jistone proteins are present in bacteria. Histone proteins are feature of Archae and eukarya. The function of gene expression efficiently. The presence of hione proteins serve as charachterestic ancestral feature between archae and eukarya.
3. The option is B. Ceramide surveys as basic structural unit of all sphingolipids. The are product of long fatty acid chain with sphingosine attached. Sphingolipid lack glycerolbackbones. Sphingolipids are found in both plants and animals. They are composed of a polar head and two non polar tail.