BIOL 252 Human Anatomy & Physiology II w/Lab |
Module 3 Exam Review 50+ Questions and Answers -
Summary | LockDown Browser | Portage Learning
Question 1 (Vessel histology – atherosclerosis surgery) A 62-year-old male with
hypertension undergoes carotid endarterectomy. The pathologist notes the
excised vessel has a tunica intima with endothelial cells and subendothelial layer,
a tunica media with 40-50 elastic lamellae and smooth muscle, and a tunica
externa with vasa vasorum. A distal branch shows more smooth muscle
dominance and fewer elastics. Refer to the aortic arch image above for context.
Identify the vessel types, explain how elastic recoil aids diastolic flow (Windkessel
effect), and calculate resistance change if plaque halves the radius (Poiseuille:
resistance ∝ 1/r^4, initial r=1). Predict long-term BP impact via RAAS if untreated.
A. Elastic artery (carotid) vs. muscular; recoil maintains pressure; 16x increase; ↑
renin → hypertension
B. Muscular vs. arteriole; contraction regulates flow; 8x increase; no BP change
C. Elastic vs. vein; valves aid return; 4x increase; ↓ volume
D. Vein vs. venule; capacitance stores blood; unchanged resistance
Correct Answer :- A Explanation: Elastic arteries (e.g., carotid from arch) handle
pulsatile flow; muscular distribute regionally. Halving r: 1/(0.5)^4=16.
Atherosclerosis → low perfusion → RAAS activation.
Question 2 (Aortic arch – dissection scenario) Using the labeled aortic arch
cadaver image above, a 68-year-old with Marfan syndrome has a type A
dissection originating at the brachiocephalic trunk. Trace flow from LV to left arm,
, naming branches, and explain why left subclavian occlusion risks arm ischemia
despite collaterals. If MAP=75 mmHg (110/60), calculate pulse pressure and initial
compensation (baroreceptors → CN IX/X → medulla → sympathetics). Discuss
autoregulation failure below 50 mmHg.
A. LV → ascending aorta → arch → left subclavian → axillary; limited collaterals;
PP=50; ↑ HR/constriction
B. LV → descending → iliac; full compensation; PP=40; RAAS only
C. LV → pulmonary; no risk; PP=50; ANP
D. LV → IVC; venous; PP=70; ADH
Correct: A Explanation: Arch branches: brachiocephalic, left carotid, left
subclavian. Dissection disrupts flow; PP=110-60=50. Baroreceptors trigger
sympathetics; low MAP → tissue hypoxia.
youtube.com
Abdominal Aorta - Duodenum, Pancreas and Abdominal Aorta SDV - YouTube
Question 3 (BP regulation – ACEI orthostasis) A 59-year-old diabetic on lisinopril
stands and BP falls from 135/85 (MAP=102) to 95/55 (MAP=68). Using the
Module 3 Exam Review 50+ Questions and Answers -
Summary | LockDown Browser | Portage Learning
Question 1 (Vessel histology – atherosclerosis surgery) A 62-year-old male with
hypertension undergoes carotid endarterectomy. The pathologist notes the
excised vessel has a tunica intima with endothelial cells and subendothelial layer,
a tunica media with 40-50 elastic lamellae and smooth muscle, and a tunica
externa with vasa vasorum. A distal branch shows more smooth muscle
dominance and fewer elastics. Refer to the aortic arch image above for context.
Identify the vessel types, explain how elastic recoil aids diastolic flow (Windkessel
effect), and calculate resistance change if plaque halves the radius (Poiseuille:
resistance ∝ 1/r^4, initial r=1). Predict long-term BP impact via RAAS if untreated.
A. Elastic artery (carotid) vs. muscular; recoil maintains pressure; 16x increase; ↑
renin → hypertension
B. Muscular vs. arteriole; contraction regulates flow; 8x increase; no BP change
C. Elastic vs. vein; valves aid return; 4x increase; ↓ volume
D. Vein vs. venule; capacitance stores blood; unchanged resistance
Correct Answer :- A Explanation: Elastic arteries (e.g., carotid from arch) handle
pulsatile flow; muscular distribute regionally. Halving r: 1/(0.5)^4=16.
Atherosclerosis → low perfusion → RAAS activation.
Question 2 (Aortic arch – dissection scenario) Using the labeled aortic arch
cadaver image above, a 68-year-old with Marfan syndrome has a type A
dissection originating at the brachiocephalic trunk. Trace flow from LV to left arm,
, naming branches, and explain why left subclavian occlusion risks arm ischemia
despite collaterals. If MAP=75 mmHg (110/60), calculate pulse pressure and initial
compensation (baroreceptors → CN IX/X → medulla → sympathetics). Discuss
autoregulation failure below 50 mmHg.
A. LV → ascending aorta → arch → left subclavian → axillary; limited collaterals;
PP=50; ↑ HR/constriction
B. LV → descending → iliac; full compensation; PP=40; RAAS only
C. LV → pulmonary; no risk; PP=50; ANP
D. LV → IVC; venous; PP=70; ADH
Correct: A Explanation: Arch branches: brachiocephalic, left carotid, left
subclavian. Dissection disrupts flow; PP=110-60=50. Baroreceptors trigger
sympathetics; low MAP → tissue hypoxia.
youtube.com
Abdominal Aorta - Duodenum, Pancreas and Abdominal Aorta SDV - YouTube
Question 3 (BP regulation – ACEI orthostasis) A 59-year-old diabetic on lisinopril
stands and BP falls from 135/85 (MAP=102) to 95/55 (MAP=68). Using the
