& Physiology I Q&A | Anatomy
1. The functional unit of compact bone is the:
A) Osteon
B) Trabecula
C) Lamella
D) Canaliculus
Correct Answer: Osteon
Rationale: The osteon (Haversian system) is the structural and functional unit
of compact bone. It consists of concentric rings of bone matrix (lamellae)
surrounding a central canal containing blood vessels and nerves.
2. The type of bone cell responsible for bone resorption (breakdown) is the:
A) Osteoblast
B) Osteocyte
C) Osteoclast
D) Chondrocyte
Correct Answer: Osteoclast
Rationale: Osteoclasts are large, multinucleated cells responsible for bone
resorption (breakdown). Osteoblasts deposit bone, osteocytes maintain the
bone matrix, and chondrocytes are cartilage cells.
3. The tiny canals that connect osteocytes to each other and the central
canal are called:
A) Lacunae
B) Canaliculi
C) Lamellae
D) Trabeculae
Correct Answer: Canaliculi
,Rationale: Canaliculi are tiny canals that house the cytoplasmic extensions of
osteocytes, allowing for the exchange of nutrients and waste between
osteocytes and the central canal.
4. The space that an osteocyte occupies is called a:
A) Canaliculus
B) Lamella
C) Lacuna
D) Haversian canal
Correct Answer: Lacuna
Rationale: Osteocytes reside in small spaces called lacunae, which are
located between the lamellae of compact bone.
5. Red bone marrow is primarily responsible for:
A) Storing fat
B) Producing blood cells
C) Producing bone cells
D) Storing minerals
Correct Answer: Producing blood cells
Rationale: Red bone marrow is the site of hematopoiesis, the production of
red blood cells, white blood cells, and platelets. Yellow bone marrow stores
fat.
6. The end of a long bone is called the:
A) Diaphysis
B) Metaphysis
C) Epiphysis
D) Periosteum
,Correct Answer: Epiphysis
Rationale: The epiphysis is the end of a long bone. It is typically wider than
the diaphysis (shaft) and is covered with articular cartilage.
7. The shaft of a long bone is called the:
A) Diaphysis
B) Epiphysis
C) Metaphysis
D) Medullary cavity
Correct Answer: Diaphysis
Rationale: The diaphysis is the shaft or central portion of a long bone. It is
composed primarily of compact bone and contains the medullary cavity.
8. The region of a long bone between the diaphysis and the epiphysis is the:
A) Periosteum
B) Endosteum
C) Metaphysis
D) Articular cartilage
Correct Answer: Metaphysis
Rationale: The metaphysis is the region of a long bone between the diaphysis
and the epiphysis. It contains the epiphyseal plate (growth plate) in growing
bones.
9. The membrane that lines the medullary cavity is the:
A) Periosteum
B) Endosteum
C) Perichondrium
D) Synovial membrane
, Correct Answer: Endosteum
Rationale: The endosteum is a thin connective tissue membrane that lines
the internal surfaces of bones, including the medullary cavity. The
periosteum covers the external surface of bones.
10. The axial skeleton includes which of the following?
A) Bones of the upper and lower limbs
B) The pectoral and pelvic girdles
C) Bones of the skull, vertebral column, and rib cage
D) The clavicle and scapula
Correct Answer: Bones of the skull, vertebral column, and rib cage
Rationale: The axial skeleton consists of the bones of the skull, vertebral
column, and thoracic cage (ribs and sternum). The appendicular skeleton
includes the limbs and girdles.
11. Which of the following is NOT a cranial bone?
A) Frontal
B) Parietal
C) Temporal
D) Mandible
Correct Answer: Mandible
Rationale: The mandible is a facial bone. The cranial bones include the
frontal, parietal, temporal, occipital, sphenoid, and ethmoid bones.
12. The suture that connects the frontal bone to the parietal bones is the:
A) Sagittal suture
B) Coronal suture
C) Lambdoid suture