Support & Movement MCQs set 3 for PMC National MDCAT Biology — 20 solved questions.
Q1. A 25-year-old woman with osteoporosis is advised to consume calcium-rich foods. Which bone cell is responsible for calcium absorption?
Answer: Osteoblast
Explanation: Osteoblasts help in bone formation by absorbing calcium; Osteoclast is wrong as it breaks down bone.
Q2. A patient with a fracture is diagnosed with delayed healing. Which vitamin deficiency is most likely the cause?
Answer: Vitamin D
Explanation: Vitamin D is crucial for calcium absorption and bone healing; Vitamin C is important but not directly related to calcium.
Q3. A 30-year-old man suffers a muscle strain during weightlifting. Which type of muscle fiber is most prone to fatigue?
Answer: Fast-twitch
Explanation: Fast-twitch fibers are used for high-intensity activities and fatigue quickly; Slow-twitch fibers are more endurance-oriented.
Q4. A person with a severed spinal cord experiences paralysis. Which type of glial cell is responsible for myelination in the CNS?
Answer: Oligodendrocyte
Explanation: Oligodendrocytes myelinate CNS neurons; Schwann cells do the same in the PNS.
Q5. An elderly person complains of joint pain and stiffness. Which type of cartilage is found in joints?
Answer: Hyaline cartilage
Explanation: Hyaline cartilage covers articular surfaces; Fibrocartilage is found in intervertebral discs.
Q6. A young athlete experiences a shoulder injury during a fall. Which ligament is most likely to be injured in a shoulder dislocation?
Answer: Glenohumeral ligament
Explanation: Glenohumeral ligament stabilizes the shoulder joint; Coracohumeral ligament also supports but is not the primary stabilizer.
Q7. A person is diagnosed with a condition where bones become soft and deformed. Which mineral deficiency is most likely the cause?
Answer: Calcium
Explanation: Calcium is crucial for bone hardness; Phosphorus is also important but Calcium is more directly related to the condition described.
Q8. A 40-year-old woman is diagnosed with rheumatoid arthritis. Which type of joint is most commonly affected?
Answer: Synovial joint
Explanation: Synovial joints are characterized by a synovial cavity and are commonly affected in rheumatoid arthritis; Fibrous and cartilaginous joints are not typically involved.
Q9. A patient is unable to move their arm due to muscle paralysis. Which neurotransmitter is responsible for transmitting signals from motor neurons to muscles?
Answer: Acetylcholine
Explanation: Acetylcholine is the neurotransmitter at neuromuscular junctions; Dopamine is involved in other neural pathways.
Q10. A 60-year-old man experiences a gradual decline in muscle mass. Which hormone is known to promote muscle protein synthesis?
Answer: Testosterone
Explanation: Testosterone promotes muscle protein synthesis; Cortisol can have catabolic effects on muscle.
Q11. A person suffers a deep cut that damages the tendon. Which type of connective tissue is tendons made of?
Answer: Dense regular connective tissue
Explanation: Tendons are made of dense regular connective tissue; Dense irregular connective tissue is found in dermis.
Q12. A 20-year-old athlete is diagnosed with a stress fracture. Which bone cell is responsible for bone resorption?
Answer: Osteoclast
Explanation: Osteoclasts resorb bone; Osteoblasts are involved in bone formation.
Q13. An elderly person has difficulty walking due to degeneration of joints. Which type of joint is most likely affected?
Answer: Synovial
Explanation: Synovial joints are weight-bearing and prone to degeneration; Cartilaginous joints can also degenerate but are not as commonly affected in the same way.
Q14. A person is born with a condition where the bones are brittle and prone to fractures. Which condition is most likely?
Answer: Osteogenesis imperfecta
Explanation: Osteogenesis imperfecta is a genetic disorder causing brittle bones; Osteoporosis is a condition of bone loss typically in older adults.
Q15. A patient complains of back pain due to a herniated disc. Which type of cartilage is found in intervertebral discs?
Answer: Fibrocartilage
Explanation: Fibrocartilage is found in intervertebral discs; Hyaline cartilage covers articular surfaces.
Q16. A 35-year-old man is diagnosed with a condition that causes progressive muscle weakness. Which organelle is most likely to be involved?
Answer: Mitochondria
Explanation: Mitochondria are crucial for muscle energy production; Sarcoplasmic reticulum is involved in calcium storage.
Q17. A person experiences muscle cramps during intense exercise. Which ion is most likely to be involved in muscle contraction?
Answer: Calcium
Explanation: Calcium ions are crucial for muscle contraction; Sodium and Potassium are involved in the action potential.
Q18. A patient is diagnosed with a bone infection. Which cell type is most likely to be involved in the immune response?
Answer: Macrophage
Explanation: Macrophages are part of the immune response; Osteoclasts can be involved in bone pathology but are not immune cells.
Q19. A 50-year-old woman experiences a gradual loss of bone density. Which hormone is most likely to be involved?
Answer: Estrogen
Explanation: Estrogen helps maintain bone density; Decrease in estrogen post-menopause is linked to osteoporosis.
Q20. A person suffers a severe injury that damages the periosteum. Which layer is responsible for bone growth and repair?
Answer: Periosteum
Explanation: Periosteum is a layer that covers bone and is involved in growth and repair; Endosteum lines the inner surface of bone.