Free Support and Movement MCQs with Answers

11. The neurotransmitter released at the neuromuscular junction of skeletal muscle is

• A. noradrenaline
• B. dopamine
• C. acetylcholine
• D. GABA

Explanation: Acetylcholine diffuses across the synaptic cleft and depolarises the sarcolemma, and the resulting action potential spreads down the T tubules to release calcium. The enzyme cholinesterase then destroys it quickly, so each nerve impulse produces one twitch rather than continuous contraction. Nerve gases and some insecticides are lethal because they block that enzyme.

12. The hip joint is an example of a

• A. hinge joint
• B. ball and socket joint
• C. pivot joint
• D. gliding joint

Explanation: The rounded head of the femur sits in the cup shaped acetabulum, which allows movement in all planes plus rotation, the widest range any joint provides. The shoulder is the other ball and socket joint and is even more mobile, but is therefore more easily dislocated because its socket is shallower. A hinge joint such as the elbow moves in one plane only.

13. Which joint allows movement in one plane only?

• A. Elbow
• B. Shoulder
• C. Hip
• D. Wrist

Explanation: The elbow is a hinge joint, so it permits flexion and extension but no rotation, in the same way as the knee and the joints of the fingers. The shoulder and hip are ball and socket joints moving in every plane, and the wrist is a condyloid joint allowing movement in two planes. Restricting a joint to one plane is what makes it stable enough to bear load.

14. Rotation of the head from side to side, as in saying no, occurs at the

• A. knee joint
• B. shoulder joint
• C. joint between the skull and the atlas
• D. joint between the atlas and the axis

Explanation: The atlas rotates around the odontoid process of the axis, and this pivot joint carries the skull with it. The joint between the skull and the atlas is the tempting answer, but that one is a hinge type movement giving the nodding of yes, not rotation. Damage at this level is dangerous because the spinal cord passes through both vertebrae.

15. The function of synovial fluid is

• A. to lubricate the joint and nourish the articular cartilage
• B. to produce red blood cells
• C. to store calcium for the body
• D. to carry nerve impulses across the joint

Explanation: Synovial fluid is secreted by the synovial membrane into the joint cavity, where it reduces friction between the cartilage surfaces and absorbs shock, and since articular cartilage has no blood supply the fluid also delivers its oxygen and nutrients. Red cell formation happens in red bone marrow and calcium is stored in the bone matrix, neither of which is a role of the fluid.

16. Osteoarthritis is caused by

• A. an autoimmune attack on the synovial membrane
• B. deposition of uric acid crystals in the joint
• C. gradual wear and degeneration of the articular cartilage
• D. bacterial infection of the joint cavity

Explanation: Osteoarthritis is a mechanical, degenerative condition in which the articular cartilage thins with age and use until bone rubs on bone, so it strikes the weight bearing knee and hip of older and overweight people first. Autoimmune attack on the synovial membrane is rheumatoid arthritis, a different disease with a different cause, and uric acid deposition is gout.

17. Rheumatoid arthritis is best described as

• A. a purely degenerative disease of old age
• B. an autoimmune inflammation of the synovial membrane
• C. a deficiency of calcium in the diet
• D. a fungal infection of the bone marrow

Explanation: In rheumatoid arthritis the immune system attacks the body's own synovial membrane, which becomes inflamed and thickened and eventually destroys the cartilage and bone beneath, so treatment aims at suppressing immunity rather than at replacing cartilage. It typically affects the small joints of the hands symmetrically and can begin in young adults, unlike osteoarthritis. Calcium deficiency causes rickets and osteomalacia instead.

18. The severe joint pain of gout, most often felt in the big toe, is caused by the deposition of

• A. calcium phosphate
• B. cholesterol
• C. collagen fibres
• D. sodium urate crystals

Explanation: Gout follows a raised blood level of uric acid, the end product of purine breakdown, which crystallises as sodium urate in a cool peripheral joint and provokes intense inflammation. This is why treatment lowers uric acid production or increases its excretion and why purine rich foods such as red meat and organ meat are restricted. Calcium salts harden bone rather than inflame joints.

19. In compact bone, the concentric rings of matrix laid down around a central canal form a structure called

• A. a Haversian system
• B. a sarcomere
• C. a lacuna
• D. the periosteum

Explanation: A Haversian system, or osteon, is the cylindrical unit of compact bone: rings of hard matrix around a canal carrying a blood vessel and a nerve, with osteocytes trapped in small spaces called lacunae between the rings. The lacuna is therefore part of the system rather than the system itself. The periosteum is the fibrous sheath on the outside of the bone.

20. The cartilage that covers the articulating surfaces of bones in a synovial joint is

• A. fibrous cartilage
• B. elastic cartilage
• C. calcified cartilage
• D. hyaline cartilage

Explanation: Hyaline cartilage is smooth, glassy and slightly compressible, so it lets bone ends slide over each other with very little friction while cushioning the load. Fibrous cartilage is tougher and appears where shock absorption matters more than smoothness, as in the intervertebral discs and the menisci of the knee. Elastic cartilage supports the pinna of the ear and the epiglottis.