Nokea
The finger-like extensions inside the small intestine are called _____ and increase the surface area.
- A. microvilli
- B. villi
- C. lacteals
- D. lumens
Correct Answer: B
Rationale: The correct answer is B: villi. Villi are finger-like projections inside the small intestine that increase the surface area for nutrient absorption. They contain blood vessels and lacteals. Microvilli (A) are tiny projections on the surface of villi that further increase surface area. Lacteals (C) are lymphatic vessels within villi that absorb fats. Lumens (D) refer to the inner space of a tubular structure and are not the finger-like extensions inside the small intestine.
You may also like to solve these questions
During muscle contraction, local metabolites act to vasodilate arterioles supplying the working muscle(s). Which of the following would NOT contribute to a local vasodilation?
- A. an increase in carbon dioxide
- B. an increase in hydrogen ions
- C. an increase in oxygen
- D. none of the above contribute to vasodilation
Correct Answer: C
Rationale: The correct answer is C because an increase in oxygen does not contribute to local vasodilation during muscle contraction. Oxygen is typically consumed by working muscles and does not act as a vasodilator. On the other hand, increases in carbon dioxide and hydrogen ions lead to vasodilation by stimulating the release of vasodilatory substances. Choice D is incorrect because oxygen, in this context, does not contribute to vasodilation like carbon dioxide and hydrogen ions do.
The duodenum and jejunum are the main site for absorption of the following except:
- A. Glucose
- B. Vitamin C
- C. Fat-soluble vitamins
- D. Bile salts
Correct Answer: D
Rationale: The correct answer is D: Bile salts. Bile salts are primarily absorbed in the terminal ileum, not in the duodenum or jejunum. The duodenum and jejunum are mainly responsible for absorbing nutrients like glucose, fat-soluble vitamins, and vitamin C. Bile salts aid in the digestion and absorption of fats, but they are reabsorbed in the ileum to be recycled. Therefore, the duodenum and jejunum are not the main sites for the absorption of bile salts.
Stimulation of the parasympathetic neurons in the GI tract from Auerbach's or myenteric plexus will cause
- A. inhibition of local secretions.
- B. inhibition of peristalsis.
- C. stimulation of local secretions.
- D. stimulation of peristalsis
Correct Answer: D
Rationale: Stimulation of parasympathetic neurons in the GI tract from Auerbach's or myenteric plexus leads to the release of acetylcholine, which enhances GI motility and peristalsis. This is because acetylcholine acts on smooth muscle and stimulates contractions, promoting movement of food through the GI tract. Therefore, the correct answer is D.
A: Inhibition of local secretions is incorrect as parasympathetic stimulation usually enhances glandular secretions in the GI tract.
B: Inhibition of peristalsis is incorrect because parasympathetic stimulation typically increases peristalsis.
C: Stimulation of local secretions is incorrect as parasympathetic stimulation usually promotes secretion but does not inhibit it.
Which manifestations may be seen in the patient with cirrhosis related to esophageal varices?
- A. Jaundice, peripheral edema, and ascites from increased intrahepatic pressure and dysfunction
- B. Loss of the small bile ducts and cholestasis and cirrhosis in patients with other autoimmune disorders
- C. Development of collateral channels of circulation in inelastic, fragile esophageal veins as a result of portal hypertension
- D. Scarring and nodular changes in the liver lead to compression of the veins and sinusoids, causing resistance of blood flow through the liver from the portal vein
Correct Answer: C
Rationale: Esophageal varices are caused by the development of collateral channels of circulation in the fragile, inelastic esophageal veins due to portal hypertension in cirrhosis.
A large number of children at a public school have developed profuse diarrhea and bloody stools. The school nurse suspects food poisoning related to food from the school cafeteria and requests analysis and culture of which food?
- A. Chicken
- B. Ground beef
- C. Commercially canned fish
- D. Salads with mayonnaise dressing
Correct Answer: B
Rationale: Ground beef is commonly associated with foodborne illnesses caused by E. coli, which can result in bloody diarrhea.