Free Human Skeleton MCQs with Answers

1. The number of bones in the skeleton of a normal adult human is

• A. 200
• B. 206
• C. 213
• D. 306

Explanation: An adult has 206 bones, 80 in the axial skeleton and 126 in the appendicular skeleton. A newborn has roughly 300 separate bones, and the number falls as several of them fuse during growth, for example the ilium, ischium and pubis into one hip bone and the five sacral vertebrae into the sacrum. That fusion is why the infant figure is the standard distractor.

2. Which of the following bones belongs to the axial skeleton?

• A. Femur
• B. Clavicle
• C. Sternum
• D. Scapula

Explanation: The axial skeleton is the central supporting column: skull, vertebral column, ribs and sternum. The clavicle and scapula are tempting because they lie in the trunk, but they form the pectoral girdle, which attaches the arms and so belongs to the appendicular skeleton along with the femur and all other limb bones.

3. The number of cervical vertebrae in the human vertebral column is

• A. 5
• B. 12
• C. 4
• D. 7

Explanation: There are seven cervical vertebrae, and the number is seven in almost all mammals, including the giraffe, whose neck is long because each vertebra is long. The full adult column has 33 vertebrae in total: 7 cervical, 12 thoracic, 5 lumbar, 5 fused as the sacrum and 4 fused as the coccyx. Twelve is the thoracic count, which is the usual mix up.

4. The longest and strongest bone of the human body is the

• A. humerus
• B. tibia
• C. femur
• D. fibula

Explanation: The femur is the thigh bone, roughly a quarter of a person's height, and it carries the whole body weight during walking, so its shaft is built to resist very large compressive loads. The tibia is the next longest and also weight bearing, which makes it the closest distractor. The fibula lies beside the tibia but bears almost no weight and mainly gives muscle attachment.

5. 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.

6. The hardness of bone is due to the deposition of

• A. salts of calcium, such as calcium phosphate
• B. silica particles
• C. sodium chloride crystals
• D. chitin fibres

Explanation: Bone combines a flexible framework of collagen with hard calcium salts, giving both strength and a little spring. Without the mineral component bone would bend, and without collagen it would shatter, which is why both parts matter.

7. The number of pairs of true ribs in the human body is

• A. 5
• B. 7
• C. 10
• D. 12

Explanation: Of the twelve pairs of ribs, the first seven attach directly to the sternum by their own cartilages and are called true ribs. The next three pairs are false ribs sharing cartilage, and the last two are floating ribs with no front attachment.

8. The human skull is made up of how many bones?

• A. 14
• B. 16
• C. 22
• D. 29

Explanation: Eight cranial bones enclose the brain and fourteen facial bones form the face, giving 22 in all. Most are fused at immovable sutures, the only freely movable bone being the mandible.

9. The number of thoracic vertebrae in the human vertebral column is

• A. 5
• B. 7
• C. 4
• D. 12

Explanation: The column has 7 cervical, 12 thoracic, 5 lumbar, 5 fused sacral and 4 fused coccygeal vertebrae. The twelve thoracic vertebrae each carry a pair of ribs, which helps fix the number in memory.

10. The pectoral girdle of the human body is composed of the

• A. clavicle and scapula
• B. femur and tibia
• C. radius and ulna
• D. sternum and ribs

Explanation: Each half of the pectoral girdle is a clavicle plus a scapula, and the arm bones attach at the shoulder socket. The pelvic girdle, in contrast, is formed by the hip bones joining the sacrum.