CBSE
Multiple Choice QuestionsIn 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
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
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
Glycogenolysis involves
Conversion of sugar into glycogen
Oxidation of Sugar
Conversion of glycogen into sugar
Conversion of glycogen into fat
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
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.
| Column I (Biological Molecule) | Column II (Function) |
| A. Glycogen | 1. Hormone |
| B. Globulin | 2. Biocatalyst |
| C. Steroid | 3. Antibody |
| D. Thrombin | 4. Storage Product |
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
Adenosine triphosphate was discovered by
Jack Lipman
A Bloor
Karl Lohmann
Emil Fisher
Which of the following amino acids is not optically active?
Glycine
Valine
Leucine
Isoleucine
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
Jacob and Monod name some enzymes as allosteric whose activity is regulated by
End product
Substrate
by product
Coenzyme
