The most basic amino acid is

(a)

Arginine

(b)

Histidine

(c)

Glycine

(d)

Glutamine

An example of feedback inhibition is

(a)

Cyanide action on cytochrome

(b)

Sulpha drug on folic acid synthesiser bacteria

(c)

Allosteric inhibition of hexokinase by glucose-6-phosphate

(d)

The inhibition of succinic dehydrogenase by malonate

Enzymes that catalyse interconversion of optical, geometrical or positional isomers are ______________

(a)

Ligases

(b)

Lyases

(c)

Hydrolases

(d)

Isomerases

Proteins perform many physiological functions. For example some functions as enzymes. One of the following represents an additional function that some proteins discharge:

(a)

Antibiotics

(b)

Pigment conferring colour to skin

(c)

Pigments making colours of flowers

(d)

Hormones

Given below is the diagrammatic representation of one of the categories of small molecular weight organic compounds in the living tissues. Identify the category shown & one blank component " X" in it.

Category	Compound
Cholesterol	Guanine
Amino acid	NH2
Nucleotide	Adenine
Nucleoside	Uracil

Distinguish between nitrogenous base and a base found in inorganic chemistry.

What are the factors affecting the rate of enzyme reaction?

Briefly outline the classification of enzymes.

Write the characteristic features of DNA.

Describe the types of RNA.