Try each question on your own first. Use the Show Answer button only after you have selected your option, then read the explanation and revise the related concept from your chapter notes.
1. Which type of movement is exhibited by human macrophages and leucocytes?
A. Amoeboid movement
B. Ciliary movement
C. Muscular movement
D. Flagellar movement
Answer: A. Amoeboid movement
Explanation: Immune cells like macrophages and leucocytes move through tissues using pseudopodia, which is amoeboid movement.
2. Ciliary movement in humans occurs predominantly in the lining of:
A. Reproductive tract and trachea
B. Gastrointestinal tract
C. Blood vessels
D. Skeletal muscles
Answer: A. Reproductive tract and trachea
Explanation: Ciliated epithelium lines the respiratory tract (trachea) to remove dust and the female reproductive tract (fallopian tube) to move ova.
3. How many total bones are present in the adult human axial skeleton?
A. 80
B. 126
C. 206
D. 22
Answer: A. 80
Explanation: The adult human skeleton consists of 206 bones, divided into the axial skeleton (80 bones) and appendicular skeleton (126 bones).
4. The functional contractile unit of a muscle fibre bounded by two successive Z-lines is called:
A. Sarcomere
B. Sarcolemma
C. Sarcoplasm
D. Myofibril
Answer: A. Sarcomere
Explanation: The portion of a myofibril between two consecutive Z-lines is considered the functional unit of contraction, called a sarcomere.
5. Which protein forms the thick filaments of a myofibril?
A. Myosin
B. Actin
C. Troponin
D. Tropomyosin
Answer: A. Myosin
Explanation: Thick filaments are composed mainly of the protein myosin, while thin filaments consist of actin, tropomyosin, and troponin.
6. During muscle contraction, which of the following bands/zones shortens and eventually disappears?
A. H-zone
B. A-band
C. Z-line thickness
D. Myosin filament length
Answer: A. H-zone
Explanation: As thin filaments slide over thick filaments during contraction, the I-bands reduce and the H-zone narrows/disappears, while the A-band retains its length.
7. Which ion released from the sarcoplasmic reticulum binds to troponin to initiate muscle contraction?
A. Calcium ions (Ca2+)
B. Sodium ions (Na+)
C. Potassium ions (K+)
D. Magnesium ions (Mg2+)
Answer: A. Calcium ions (Ca2+)
Explanation: Release of Ca2+ into the sarcoplasm leads to its binding with troponin C on actin filaments, unmasking active sites for myosin heads.
8. The total number of cranial bones present in the human skull is:
A. 8
B. 14
C. 12
D. 6
Answer: A. 8
Explanation: The cranium consists of 8 bones (1 frontal, 2 parietal, 2 temporal, 1 occipital, 1 sphenoid, 1 ethmoid), while the facial region has 14 bones.
9. The first cervical vertebra that articulates with the occipital condyles is called:
A. Atlas
B. Axis
C. Sacrum
D. Lumbar
Answer: A. Atlas
Explanation: The first cervical vertebra is the atlas (C1), which articulates with the occipital condyles of the skull.
10. How many pairs of true ribs are present in the human thoracic cage?
A. 7 pairs (1st to 7th)
B. 3 pairs (8th to 10th)
C. 2 pairs (11th and 12th)
D. 12 pairs
Answer: A. 7 pairs (1st to 7th)
Explanation: The first 7 pairs of ribs are called true ribs (vertebrosternal ribs) because they directly connect dorsally to vertebrae and ventrally to the sternum via hyaline cartilage.
11. Rib pairs 11 and 12 are called floating ribs because:
A. Their ventral ends are not connected to the sternum
B. They do not articulate with the vertebral column
C. They lack hyaline cartilage
D. They are made entirely of cartilage
Answer: A. Their ventral ends are not connected to the sternum
Explanation: The 11th and 12th pairs of ribs are floating ribs because their anterior ends remain free and do not attach to the sternum or other ribs.
12. The collar bone in the human pectoral girdle is scientifically known as the:
A. Clavicle
B. Scapula
C. Sternum
D. Humerus
Answer: A. Clavicle
Explanation: Each pectoral girdle half consists of a clavicle (collar bone) and a scapula (shoulder blade).
13. A cup-shaped cavity in the pelvic girdle that articulates with the head of the femur is called the:
A. Acetabulum
B. Glenoid cavity
C. Foramen magnum
D. Obturator foramen
Answer: A. Acetabulum
Explanation: The acetabulum is formed by the fusion of ilium, ischium, and pubis, accommodating the head of the thigh bone (femur).
14. The glenoid cavity articulates the head of which bone with the pectoral girdle?
A. Humerus
B. Femur
C. Radius
D. Scapula
Answer: A. Humerus
Explanation: The depression below the acromion process called the glenoid cavity articulates with the head of the humerus to form the shoulder joint.
15. What type of joint is found between the humerus and pectoral girdle?
A. Ball and socket joint
B. Hinge joint
C. Pivot joint
D. Gliding joint
Answer: A. Ball and socket joint
Explanation: The shoulder joint is a ball and socket synovial joint allowing wide movement in multiple directions.
16. The joint between Atlas and Axis vertebrae is an example of a:
A. Pivot joint
B. Hinge joint
C. Gliding joint
D. Saddle joint
Answer: A. Pivot joint
Explanation: The atlanto-axial joint between atlas and axis is a pivot joint permitting side-to-side rotation of the head.
17. Sutures present between skull bones belong to which category of joints?
A. Fibrous joints (Immovable)
B. Cartilaginous joints
C. Synovial joints
D. Gliding joints
Answer: A. Fibrous joints (Immovable)
Explanation: Skull sutures are immovable fibrous joints fused end-to-end with dense fibrous connective tissue.
18. An autoimmune disorder affecting neuromuscular junctions leading to fatigue, weakening, and paralysis of skeletal muscles is:
A. Myasthenia gravis
B. Muscular dystrophy
C. Tetany
D. Rheumatoid arthritis
Answer: A. Myasthenia gravis
Explanation: Myasthenia gravis is an autoimmune disease where antibodies block or destroy acetylcholine receptors at neuromuscular junctions.
19. Rapid spasms or wild contractions in muscle due to low Ca2+ level in body fluids is called:
A. Tetany
B. Tetanus
C. Gout
D. Osteoporosis
Answer: A. Tetany
Explanation: Low Ca2+ levels in body fluids cause hypocalcemic tetany, characterized by involuntary sustained muscle spasms.
20. Age-related disorder characterized by decreased bone mass and increased risk of fractures, often due to decreased estrogen levels, is:
A. Osteoporosis
B. Osteoarthritis
C. Gout
D. Myasthenia gravis
Answer: A. Osteoporosis
Explanation: Osteoporosis is a skeletal disorder where bone density declines, commonly seen in post-menopausal women due to reduced estrogen.
21. Inflammation of joints due to accumulation of uric acid crystals is known as:
A. Gout
B. Rheumatoid arthritis
C. Osteoarthritis
D. Spondylitis
Answer: A. Gout
Explanation: Gout is a form of arthritis caused by deposition of monosodium urate/uric acid crystals in joint cavities.
22. What red pigment present in muscle fibers stores oxygen for cellular respiration?
A. Myoglobin
B. Hemoglobin
C. Hemocyanin
D. Cytochrome
Answer: A. Myoglobin
Explanation: Myoglobin is an iron- and oxygen-binding protein found in muscle tissues, especially in aerobic red muscle fibers.
23. Total number of bones present in a single human upper limb (arm) is:
Explanation: The patella is a cup-shaped bone that covers the knee joint ventrally.
25. Vertebrochondral ribs (false ribs) in humans include rib pairs:
A. 8th, 9th, and 10th pairs
B. 1st to 7th pairs
C. 11th and 12th pairs
D. 1st to 5th pairs
Answer: A. 8th, 9th, and 10th pairs
Explanation: Rib pairs 8, 9, and 10 do not articulate directly with the sternum but join the 7th rib via hyaline cartilage, hence called false/vertebrochondral ribs.
26. Human vertebral formula is correctly written as:
A. C7 T12 L5 S(5) Co(4)
B. C8 T12 L5 S5 Co4
C. C7 T10 L5 S(5) Co(1)
D. C7 T12 L7 S(5) Co(4)
Answer: A. C7 T12 L5 S(5) Co(4)
Explanation: Human vertebral column has 26 adult units: Cervical 7, Thoracic 12, Lumbar 5, Sacral 1 (fused 5), and Coccygeal 1 (fused 4).
27. Monomeric protein unit of a thick filament (myosin) is called:
A. Meromyosin
B. F-actin
C. G-actin
D. Troponin T
Answer: A. Meromyosin
Explanation: Each myosin filament is a polymer composed of many monomeric proteins called meromyosins (Heavy Meromyosin and Light Meromyosin).
28. Joint between carpals in the wrist is an example of a:
A. Gliding joint
B. Hinge joint
C. Saddle joint
D. Pivot joint
Answer: A. Gliding joint
Explanation: The intercarpal joint between wrist bones is a gliding synovial joint allowing limited sliding movements.
29. Joint between carpal and metacarpal of thumb is classified as a:
A. Saddle joint
B. Gliding joint
C. Pivot joint
D. Hinge joint
Answer: A. Saddle joint
Explanation: The carpometacarpal joint of the human thumb is a classic example of a saddle joint providing flexible mobility.
30. Smooth muscle fibers are characterized as:
A. Involuntary, non-striated, and spindle-shaped
B. Voluntary, striated, and cylindrical
C. Involuntary, striated, and branched
D. Voluntary, non-striated, and multinucleated
Answer: A. Involuntary, non-striated, and spindle-shaped
Explanation: Visceral or smooth muscles lack striations, are uninucleate and fusiform (spindle-shaped), and operate involuntarily.
This page contains a chapter-wise objective practice set. Try the questions without checking the answer first, then use the explanation to understand the point you missed. The current page contains 30 questions, so you can practise in smaller sets when you are revising.
Topics to keep in mind
Other Biology Chapters:
Quick revision tip
After the practice set, write down the question numbers you missed and revise only those concepts once more. This makes MCQ practice more useful than repeatedly attempting the same questions without reviewing mistakes.
