UExcel Anatomy and Physiology 4 — Questions and Answers
Question 1: Surfactant produced by Type II pneumocytes primarily functions to:
- Warm inspired air
- Reduce alveolar surface tension (Correct answer)
- Filter airborne particles
- Transport oxygen to blood
Correct answer: Reduce alveolar surface tension
Pulmonary surfactant reduces surface tension in alveoli, preventing their collapse (atelectasis) during exhalation.
Question 2: The tidal volume of a healthy adult at rest is approximately:
- 150 mL
- 500 mL (Correct answer)
- 1,200 mL
- 4,800 mL
Correct answer: 500 mL
Tidal volume—the amount of air inhaled or exhaled in a normal breath at rest—averages approximately 500 mL in adults.
Question 3: Which structure connects the testes to the urethra and is responsible for sperm maturation?
- Seminal vesicle
- Vas deferens
- Epididymis (Correct answer)
- Prostate gland
Correct answer: Epididymis
The epididymis is a coiled tube where sperm mature and are stored before passing into the vas deferens.
Question 4: During the proliferative phase of the uterine cycle, rising estrogen levels stimulate:
- Ovulation
- Progesterone secretion
- Endometrial lining rebuild (Correct answer)
- Corpus luteum regression
Correct answer: Endometrial lining rebuild
Rising estrogen during the proliferative phase causes the endometrial lining to thicken and rebuild after menstruation.
Question 5: Which part of the nephron is primarily responsible for selective reabsorption of glucose, amino acids, and most ions?
- Glomerulus
- Proximal convoluted tubule (Correct answer)
- Loop of Henle
- Collecting duct
Correct answer: Proximal convoluted tubule
The proximal convoluted tubule reabsorbs approximately 65% of filtered water, nearly all glucose and amino acids, and most ions.
Question 6: The term 'cardiac output' is best defined as:
- The pressure difference between systole and diastole
- The volume of blood the heart ejects per beat
- Heart rate multiplied by stroke volume (Correct answer)
- The total blood volume in the body
Correct answer: Heart rate multiplied by stroke volume
Cardiac output (CO) = heart rate (HR) × stroke volume (SV), representing the volume of blood pumped by one ventricle per minute.
Question 7: Which white blood cell type releases histamine and heparin during an allergic response?
- Neutrophil
- Eosinophil
- Basophil (Correct answer)
- Monocyte
Correct answer: Basophil
Basophils (and tissue mast cells) release histamine and heparin, contributing to the inflammatory and allergic response.
UExcel Anatomy and Physiology 4
Surfactant produced by Type II pneumocytes primarily functions to: