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.

In an annelids, the contraction of circular muscle results in___________?
A Lengthening of the body.
B Shortening of the body.
C Widening of body
D Thinning of body
Correct Answer: Thinning of body
Diameter of thick filament is____________?
A 7 nm.
B 8 nm
C 16nm
D 10-100 ?m.
Correct Answer: 16nm
Which of the following animal has a hydrostatic skeleton?
A Earthworm
B Round worm
C Tape worm
D Pin worm
Correct Answer: Earthworm
A smallest contractile unit of muscle contraction called sarcomere is the area between two:
A H- zone
B M- Line
C Z- Line
D A band
Correct Answer: Z- Line
Gibberellins is an example of_________________?
A Growth inhibitor
B Growth stimulator
C Growth hormone
D None of these
Correct Answer: Growth stimulator
Which of the following statements is incorrect about skeletal muscle fibers?
A They are multinucleated.
B They are 10 – 100 ?m in diameter & surrounded by sarcolemma
C They contain O2 storing molecules called hemoglobin.
D Their cytoplasm contains high concentration of carbohydrates
Correct Answer: They contain O2 storing molecules called hemoglobin.
Epinasty is controlled by_____________?
A Gibberellins
B Abscisins
C Auxins
D Cytokinins
Correct Answer: Auxins
Why skeletal muscles are called striated muscles?
A They appear darker than smooth muscles by naked eye.
B Alternating dark and light bands appear on their surface when visualized by naked eye.
C Alternating dark and light bands appear on their surface when visualized via a microscope.
D All of these
Correct Answer: Alternating dark and light bands appear on their surface when visualized via a microscope.
Roots of a plant show______________?
A Positive phototropism and negative geotropism
B Negative phototropism and positive geotropism
C Negative tactic movement and positive tropic movement
D Positive geotropism of stem and roots
Correct Answer: Negative phototropism and positive geotropism
The contraction of which of the following muscle fibers, is controlled by hormones?
A A smooth muscle
B A cardiac muscle
C A skeletal muscle.
D All of these
Correct Answer: A smooth muscle