All Free Biology MCQs with Answers

801. The joints between the bones of the skull are

• A. freely movable synovial joints
• B. slightly movable cartilaginous joints
• C. immovable fibrous joints called sutures
• D. ball and socket joints

Explanation: Sutures interlock the skull bones with fibrous tissue, locking the case that protects the brain. Free movement here would be dangerous, which is why the only movable skull bone is the mandible.

802. The joints between the bodies of adjacent vertebrae are best described as

• A. freely movable
• B. immovable
• C. synovial
• D. slightly movable

Explanation: Cartilage discs between vertebrae allow limited movement, and the many small movements add up to the flexibility of the whole column. True free movement belongs to synovial joints such as the shoulder.

803. The elbow joint is an example of

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

Explanation: The elbow swings in one plane, flexing and extending the forearm like a door hinge. The shoulder and hip are ball and socket, while the atlas axis pair forms the pivot joint of the neck.

804. A pivot joint permits

• A. movement in all planes
• B. rotation around a single axis
• C. gliding only
• D. no movement at all

Explanation: In a pivot joint one bone rotates within a ring formed by another, as when the atlas turns on the dens of the axis to shake the head from side to side. All plane movement needs a ball and socket joint instead.

805. A gliding joint, in which nearly flat bone surfaces slide over one another, is found

• A. at the hip
• B. at the elbow
• C. between the carpal bones of the wrist
• D. between the bones of the skull

Explanation: The small bones of the wrist and ankle glide against each other, giving limited but versatile movement. The skull bones are fused and immobile, and the hip and elbow are shaped for much larger movements.

806. Arthritis is the general term for diseases that cause

• A. weakening of the muscles
• B. degeneration of the nerves
• C. inflammation of tendons only
• D. inflammation, pain and stiffness of the joints

Explanation: Whatever the cause, arthritis means an inflamed joint that is painful and stiff. The main types differ in mechanism: osteoarthritis wears cartilage away, rheumatoid arthritis is autoimmune, and gout deposits urate crystals.

807. Which of the following is a common risk factor for osteoarthritis?

• A. Increasing age
• B. A viral infection
• C. Low blood pressure
• D. Excess vitamin D

Explanation: Years of use thin the cartilage and stiffen the joints, so osteoarthritis is commonest after middle age, with obesity and joint injury adding to the risk. It is a wear and tear disease, not an infection.

808. Regular moderate exercise helps a patient with arthritis mainly because it

• A. cures the disease completely
• B. keeps the joints mobile and strengthens the muscles around them
• C. regrows the worn away cartilage
• D. dissolves calcium out of the bones

Explanation: Movement nourishes cartilage, prevents stiffness and builds supporting muscle, which unloads the joint. Exercise cannot restore lost cartilage, so its benefit is protection and function, not cure.

809. To reduce the frequency of gout attacks, a patient is usually advised to

• A. eat more organ meats
• B. avoid drinking water
• C. limit purine rich foods and alcohol
• D. stop all physical activity

Explanation: Purines from red meat and organ meats break down to uric acid, the substance that crystallises in the joints during gout, and alcohol raises its production too. Cutting these lowers urate levels and prevents flares.

810. In severe arthritis a badly damaged joint can be surgically replaced with

• A. a graft of tendon
• B. a long course of antibiotics
• C. physiotherapy alone
• D. an artificial prosthesis of metal and plastic

Explanation: Joint replacement, most often of the hip or knee, fits metal and plastic surfaces where cartilage has vanished, relieving pain and restoring movement. Antibiotics treat infection, not mechanical wear.