NCBTMB Anatomy and Physiology 5 — Questions and Answers
Question 1: Which of the following is a function of the spleen in the adult human body?
- Production of bile for digestion
- Filtration of blood and destruction of old red blood cells (Correct answer)
- Secretion of digestive enzymes
- Regulation of blood glucose levels
Correct answer: Filtration of blood and destruction of old red blood cells
The spleen filters blood, removes old or damaged red blood cells, stores platelets, and plays a role in immune surveillance.
Question 2: The brachial plexus originates from which spinal cord levels?
- C1–C5
- C5–T1 (Correct answer)
- T1–T5
- C3–C8
Correct answer: C5–T1
The brachial plexus arises from anterior rami of spinal nerves C5 through T1 and innervates the entire upper extremity.
Question 3: Which muscle is the primary flexor of the elbow and is innervated by the musculocutaneous nerve?
- Brachioradialis
- Triceps brachii
- Biceps brachii (Correct answer)
- Coracobrachialis
Correct answer: Biceps brachii
The biceps brachii is the primary elbow flexor, also supinating the forearm; it is innervated by the musculocutaneous nerve (C5–C6).
Question 4: In the digestive system, where does the majority of chemical digestion and nutrient absorption occur?
- Stomach
- Large intestine
- Small intestine (Correct answer)
- Esophagus
Correct answer: Small intestine
The small intestine, with its villi and microvilli, is the primary site of chemical digestion by enzymes and absorption of nutrients into the bloodstream.
Question 5: What is the name of the tough fibrous membrane that covers the outer surface of bone, excluding joint surfaces?
- Endosteum
- Periosteum (Correct answer)
- Perichondrium
- Synovium
Correct answer: Periosteum
The periosteum is the dense fibrous connective tissue sheath covering the outer surface of bone and contains osteogenic cells essential for bone repair and growth.
Question 6: Which structure connects the hypothalamus to the posterior pituitary gland and allows direct neural control of hormone release?
- Infundibulum (Correct answer)
- Corpus callosum
- Circle of Willis
- Hypophyseal portal system
Correct answer: Infundibulum
The infundibulum (pituitary stalk) is the neural connection between the hypothalamus and posterior pituitary, through which axons carry ADH and oxytocin for release.
Question 7: Which type of receptor detects changes in the length of a muscle and helps regulate muscle tone through the stretch reflex?
- Golgi tendon organ
- Pacinian corpuscle
- Muscle spindle (Correct answer)
- Meissner's corpuscle
Correct answer: Muscle spindle
Muscle spindles (intrafusal fibers) detect changes in muscle length and send signals to the spinal cord to initiate a stretch reflex, maintaining muscle tone.
NCBTMB Anatomy and Physiology 5
Which of the following is a function of the spleen in the adult human body?