Certified Surgical Technologist Anatomy and Physiology 4 — Questions and Answers
Question 1: Which layer of the heart wall is responsible for the contractile force of cardiac muscle?
- Epicardium
- Myocardium (Correct answer)
- Endocardium
- Pericardium
Correct answer: Myocardium
The myocardium is the thick middle muscular layer of the heart wall composed of cardiac muscle cells that generate the pumping force.
Question 2: The triangles of the neck are important surgical landmarks. The carotid triangle contains which major vessels?
- Subclavian artery and vein
- Common carotid artery, internal jugular vein, and vagus nerve (Correct answer)
- External jugular vein and brachial plexus
- Facial artery and anterior jugular vein
Correct answer: Common carotid artery, internal jugular vein, and vagus nerve
The carotid triangle contains the common carotid artery, internal jugular vein, and vagus nerve forming the carotid sheath, making it a critical surgical region.
Question 3: Which vertebral level marks the bifurcation of the abdominal aorta into the common iliac arteries?
- L1
- L2
- L4 (Correct answer)
- L5
Correct answer: L4
The abdominal aorta bifurcates into the right and left common iliac arteries at the level of the L4 vertebra, just below the umbilicus.
Question 4: In the context of surgery, which fascia encloses the rectus abdominis muscle and is commonly used as a graft or repair layer?
- Camper's fascia
- Scarpa's fascia
- Transversalis fascia
- Rectus sheath (Correct answer)
Correct answer: Rectus sheath
The rectus sheath is a strong fibrous compartment formed by the aponeuroses of the external oblique, internal oblique, and transversus abdominis muscles.
Question 5: The pleural cavity normally contains a small amount of fluid. What is its primary function?
- Providing nutrients to lung tissue
- Reducing friction during breathing (Correct answer)
- Facilitating gas exchange
- Secreting surfactant
Correct answer: Reducing friction during breathing
Pleural fluid lubricates the surfaces of the visceral and parietal pleura, reducing friction as the lungs expand and contract during respiration.
Question 6: Which bone forms the posterior wall of the orbit and is commonly fractured in a 'blowout' orbital fracture?
- Frontal bone
- Zygomatic bone
- Ethmoid bone
- Orbital floor (maxilla) (Correct answer)
Correct answer: Orbital floor (maxilla)
A blowout fracture typically involves the thin orbital floor formed by the maxilla, which buckles inward under sudden increased intraorbital pressure.
Question 7: During a prostatectomy, which nerve bundles running posterolateral to the prostate must be preserved to maintain erectile function?
- Pudendal nerve bundles
- Neurovascular bundles of Walsh (Correct answer)
- Obturator nerve bundles
- Pelvic splanchnic nerve bundles
Correct answer: Neurovascular bundles of Walsh
The neurovascular bundles of Walsh run posterolateral to the prostate and contain the cavernous nerves responsible for erectile function.
Certified Surgical Technologist Anatomy and Physiology 4
Which layer of the heart wall is responsible for the contractile force of cardiac muscle?