M C Q s D r i v e

Biology 1525 MCQs [All-Courses]

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Biology covers key concepts of life, organisms, and human systems with exam-focused notes for PPSC, FPSC, KPPSC, BPSC.,NTS, OTS, AJKPSC. Clear, concise topics help students prepare effectively for competitive tests.

Optimal temperature of enzymes present in human body is_____________?

A 27?C
B 37?C
C 47?C
D 30?C
Correct Answer: 37?C

A chemical substance which can react (in place of substrate) with the enzyme but is not transformed into product/s and thus blocks the active site temporarily or permanently is called_______________?

A Co-enzyme
B Blocker
C Inhibitor
D Cofactor
Correct Answer: Inhibitor

A substance which binds at the active site of the enzyme but does not result in the formation of the products is called________________?

A Irreversible inhibitor
B Reversible inhibitor
C Competitive inhibitor
D Non-competitive inhibitor
Correct Answer: Competitive inhibitor

Which of the statement about cell membrane is not true?

A It contains protein molecules embedded in lipid bilayer
B It is a differentially permeable membrane.
C It contains charged pores thus ions being charged particles cross cell membrance much easier than neutral particles.
D It may get infolded to engulf solid or liquid material.
Correct Answer: It contains charged pores thus ions being charged particles cross cell membrance much easier than neutral particles.

Inhibitors which block the enzyme by forming weak bond are called___________?

A Competitive inhibitors.
B Non-competitive inhibitors
C Irreversible inhibitors.
D Both a and b
Correct Answer: Both a and b

Magnifying power of electron microscope as compared to eye is____________?

A 500 X
B 250000X
C 500000X
D 250X
Correct Answer: 250000X

Malonic acid is an example of____________?

A Irreversible inhibitor
B Reversible inhibitor
C Competitive inhibitor
D Non-competitive inhibitor
Correct Answer: Competitive inhibitor

The structure of an enzyme is altered by____________?

A Irreversible inhibitor
B Reversible inhibitor
C Competitive inhibitor
D Non-competitive inhibitor
Correct Answer: Irreversible inhibitor

In cell fractionation various components of cells including its organelles can be isolated in different layers depending upon____________?

A Their physical properties like size & weight.
B Physical properties of the medium like its density.
C Their electrical properties like their charges
D Both a and b
Correct Answer: Both a and b

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____________________?

A increase in concentration of enzyme
B increase in concentration of substrate
C increase in pH
D increase in temperature
Correct Answer: increase in concentration of enzyme