Start Biology MCQs Quiz Test !
Public Service Commission Biology MCQs
Q.1: The active site of an enzyme——-?
- Never changes
- Forms no chemical bond with substrate
- Determined by structure and the specificity of the enzyme
- They are non specific in their action
C
Q.2: Factory of Ribosomal systhesis is—–?
- Cytoplasm
- Nucleus
- Nucleolus
- Endoplasmic reticulum
C
Q.3: If more substrate to already occurring enzymatic reaction is added and there is no effect on the rate of the reaction what is the form given to this situation——?
- Saturation
- Denaturation
- Composition
- Inhibition
A
Q.4: Who opposed the idea the cell is an empty space bounded by thick wall?
- Lorenz Oken
- Schwann
- Robert Brown
- Rudolph Virchow
C
Q.5: Extreme change in pH results in——-?
- Change in ionization of amino acids at the active site of the enzyme
- Change in the ionization of the substrate
- Denaturation of the enzyme
- Increase in the reaction rate
C
Q.6: Resolution power of a compound microscope is——?
- 2.0 m
- 2-4 A
- 24 m
- 24 A
A
Q.7: Excessive increase in temperature of medium causes the enzyme molecule to——?
- Activate
- Unaffected
- Denatured
- None of these
C
Q.8: If enzyme concentration is low than substrate pH and temperature values are equal to requirement then which of the following will increase rate of reaction———-?
- increase in concentration of enzyme
- increase in concentration of substrate
- increase in pH
- increase in temperature
A
Q.9: In cell fractionation various components of cells including its organelles can be isolated in different layers depending upon——?
- Their physical properties like size And weight.
- Physical properties of the medium like its density.
- Their electrical properties like their charges
- Both a and b
D
Q.10: The structure of an enzyme is altered by——?
- Irreversible inhibitor
- Reversible inhibitor
- Competitive inhibitor
- Non-competitive inhibitor
A