Part 7: Disorders of Muscles and Skeletal System
Part 7 (25 MCQs) on Disorders of Muscles and Skeletal System – Myasthenia Gravis, Muscular Dystrophy, Arthritis, Osteoporosis, Gout, Tetany, etc. from Chapter 20: Locomotion and Movement (Class 11 NCERT + NEET UG level).
Part 7: Disorders of Muscles and Skeletal System
Q1. Myasthenia gravis is caused by:
a) Vitamin D deficiency
b) Autoimmune destruction of acetylcholine receptors
c) Lack of ATP
d) Calcium deficiency
Answer: b) Autoimmune destruction of acetylcholine receptors
Explanation:
- ✅ (b) Myasthenia gravis = autoimmune disorder → muscle weakness.
- (a), (c), (d) → unrelated.
Q2. Muscular dystrophy is:
a) Genetic disorder causing progressive muscle degeneration
b) Autoimmune disorder
c) Bacterial infection
d) Viral disease
Answer: a) Genetic disorder causing progressive muscle degeneration
Explanation:
- ✅ (a) Duchenne muscular dystrophy = inherited X-linked disorder.
Q3. Arthritis is primarily a disorder of:
a) Muscles
b) Bones
c) Joints
d) Nerves
Answer: c) Joints
Explanation:
- ✅ (c) Arthritis = inflammation of joints.
Q4. Osteoporosis is caused due to:
a) Vitamin A deficiency
b) Calcium and estrogen deficiency
c) Excess protein intake
d) Lack of vitamin C
Answer: b) Calcium and estrogen deficiency
Explanation:
- ✅ (b) Bone mass loss common in post-menopausal women.
Q5. Gout is caused by accumulation of:
a) Urea
b) Uric acid
c) Lactic acid
d) Calcium salts
Answer: b) Uric acid
Explanation:
- ✅ (b) Uric acid crystals deposit in joints → painful swelling.
Q6. Tetany is caused by deficiency of:
a) Sodium
b) Calcium
c) Potassium
d) Magnesium
Answer: b) Calcium
Explanation:
- ✅ (b) Hypocalcemia → involuntary muscle spasms (tetany).
Q7. Rickets is caused by deficiency of:
a) Vitamin D
b) Vitamin A
c) Vitamin K
d) Vitamin B12
Answer: a) Vitamin D
Explanation:
- ✅ (a) Vitamin D deficiency → weak, deformed bones in children.
Q8. Osteomalacia is seen in:
a) Children (bone deformity)
b) Adults (softening of bones)
c) Elderly (joint inflammation)
d) Infants (muscle weakness)
Answer: b) Adults (softening of bones)
Explanation:
- ✅ (b) Osteomalacia = adult form of rickets.
Q9. Kyphosis is abnormal curvature of:
a) Cervical vertebrae
b) Thoracic vertebrae
c) Lumbar vertebrae
d) Sacrum
Answer: b) Thoracic vertebrae
Explanation:
- ✅ (b) Kyphosis = hunchback (thoracic curve).
Q10. Lordosis is abnormal curvature of:
a) Cervical vertebrae
b) Thoracic vertebrae
c) Lumbar vertebrae
d) Coccyx
Answer: c) Lumbar vertebrae
Explanation:
- ✅ (c) Lordosis = excessive lumbar curve.
Q11. Scoliosis is:
a) Forward bending of spine
b) Lateral bending of spine
c) Inflammation of joints
d) Bone loss
Answer: b) Lateral bending of spine
Explanation:
- ✅ (b) Scoliosis = sideways curve.
Q12. Osteoarthritis is caused by:
a) Autoimmune reaction
b) Degeneration of cartilage at joints
c) Uric acid deposition
d) Vitamin D deficiency
Answer: b) Degeneration of cartilage at joints
Explanation:
- ✅ (b) Osteoarthritis = wear-and-tear of joints.
Q13. Rheumatoid arthritis is:
a) Genetic disorder
b) Autoimmune disorder
c) Calcium deficiency disorder
d) Viral disease
Answer: b) Autoimmune disorder
Explanation:
- ✅ (b) Autoimmune → inflammation of synovial joints.
Q14. Osteoporosis commonly affects:
a) Children
b) Adolescents
c) Post-menopausal women
d) Men under 30
Answer: c) Post-menopausal women
Explanation:
- ✅ (c) Low estrogen → rapid bone density loss.
Q15. Duchenne muscular dystrophy is:
a) Autosomal recessive
b) X-linked recessive
c) Autosomal dominant
d) Viral disorder
Answer: b) X-linked recessive
Explanation:
- ✅ (b) DMD is X-linked, affects boys more.
Q16. Gout leads to deposition of crystals in:
a) Liver
b) Kidney
c) Joints
d) Heart
Answer: c) Joints
Explanation:
- ✅ (c) Uric acid crystals in synovial joints.
Q17. Which mineral is mainly affected in osteoporosis?
a) Iron
b) Calcium
c) Sodium
d) Zinc
Answer: b) Calcium
Explanation:
- ✅ (b) Decrease in calcium & bone matrix.
Q18. Cramps during exercise are due to:
a) ATP accumulation
b) Lactic acid accumulation
c) Urea accumulation
d) Oxygen excess
Answer: b) Lactic acid accumulation
Explanation:
- ✅ (b) Anaerobic glycolysis → lactic acid → cramps.
Q19. Which joint is most commonly affected in gout?
a) Knee
b) Hip
c) Big toe joint
d) Shoulder
Answer: c) Big toe joint
Explanation:
- ✅ (c) First metatarsophalangeal joint → gout attack site.
Q20. Which disease is characterized by porous and fragile bones?
a) Rickets
b) Osteoporosis
c) Arthritis
d) Gout
Answer: b) Osteoporosis
Explanation:
- ✅ (b) Bones become brittle due to mineral loss.
Q21. Which vitamin deficiency causes tetany indirectly?
a) Vitamin D
b) Vitamin B12
c) Vitamin A
d) Vitamin E
Answer: a) Vitamin D
Explanation:
- ✅ (a) Vitamin D deficiency → poor calcium absorption → hypocalcemia → tetany.
Q22. A disorder in which muscles fail to contract properly due to defective calcium channels is:
a) Myasthenia gravis
b) Hypocalcemic tetany
c) Muscular dystrophy
d) Arthritis
Answer: b) Hypocalcemic tetany
Explanation:
- ✅ (b) Low calcium → repeated spasms.
Q23. Ankylosing spondylitis primarily affects:
a) Skull
b) Vertebral column
c) Ribs
d) Sternum
Answer: b) Vertebral column
Explanation:
- ✅ (b) Ankylosing spondylitis → inflammation of vertebral joints.
Q24. Pain and stiffness in joints due to age-related wear and tear is:
a) Rheumatoid arthritis
b) Osteoarthritis
c) Gout
d) Rickets
Answer: b) Osteoarthritis
Explanation:
- ✅ (b) Common in elderly → cartilage wear.
Q25. Which disease is characterized by progressive muscle weakness and wasting?
a) Muscular dystrophy
b) Arthritis
c) Gout
d) Tetany
Answer: a) Muscular dystrophy
Explanation:
- ✅ (a) Genetic → muscle wasting, weakness.
Locomotion movement Class 11, NEET UG biology MCQs, NCERT Class 11 Biology, Chapter 20 locomotion MCQs, Human skeletal muscular system, CBSE Class 11 exam prep, Locomotion NEET practice questions, NCERT-based biology learning, Class 11 locomotion and movement MCQs, NEET locomotion and movement biology questions, Locomotion and movement NCERT quiz Class 11, MCQs on locomotion and movement for NEET, Human skeletal system NEET UG preparation, Chapter 20 biology locomotion movement questions, Locomotion movement Class 11 notes with MCQs, NCERT Class 11 biology online learning MCQs