Jacob and Monod name some enzymes as allosteric whose activity is regulated by

• End product

• Substrate

• by product

• Coenzyme

Adenosine triphosphate was discovered by

• Jack Lipman

• A Bloor

• Karl Lohmann

• Emil Fisher

Keeping is viewed the structure of cell membrane, which one of the following statements is correct with respect to the movements of liquid and proteins from one liquid monolayer to the other (flip-flop movement).

• While proteins can flip flop, liquids can not

• Neither lipids, nor proteins can flip flop

• Both lipids and proteins can flip flop

• While lipids can rarely flip-flop, proteins can not

Match the biological molecule listed under column I with their biological function listed under column II. Choose the answer which gives correct combination of alphabet of the two columns.

• A-3, B-2, C-4, D-1

• A-4, B-2, C-1, D-3

• A-2, B-4, C-3, D-1

• A-4, B-3, C-1, D-2

The enzyme hexokinase which catalysis glucose to a glucose-6-phosphate in glycolysis is inhibited by glucose-6-phosphate. This is an example of

I. Competitive inhibition

II. non-competitive inhibition

III. feedback allosteric inhibition

Which of the above statements is/are correct?

• I and II

• I and III

• Only III

• All of these

Glycogenolysis involves

• Conversion of sugar into glycogen

• Oxidation of Sugar

• Conversion of glycogen into sugar

• Conversion of glycogen into fat

An example of the competitive inhibition of an enzyme is the inhibition of

• Succinic dehydrogenase by malonic acid

• Cytochrome oxidase by cyanide

• Hexokinase by glucose-6-phosphate

• Carbonic anhydrase by carbon dioxide

48.

In the sieve elements, which one of the following is the most likely function of P-proteins?

• Deposition of callose on sieve plates

• Providing energy for active translocation

• Autolytic enzymes

• Sealing off mechanism on wounding

Two cells A and B are contiguous. Cell A has osmotic pressure 10 atm, turgor pressure-7 atm and diffusion pressure deficit 3 atm. Cell B has osmotic pressure 8 atm, turgor pressure 3 atm and diffusion pressure deficit 5 atm. The result will be

• Movement of water from cell B to A

• No movement of water

• The equilibrium between the two

• Movement of water from cell A to B

Which of the following amino acids is not optically active?

• Glycine

• Valine

• Leucine

• Isoleucine