Nursing Elites

1. The lining of the stomach and intestine is protected from self-digestion by:

• A. pepsinogen.
• B. bile.
• C. mucus.
• D. fat.

Correct answer: C

Rationale: The correct answer is C: mucus. Mucus forms a protective barrier that prevents the stomach and intestine from digesting themselves. Pepsinogen (choice A) is an inactive form of pepsin, a digestive enzyme, and does not protect the stomach lining. Bile (choice B) aids in the digestion and absorption of fats but does not protect the stomach lining. Fat (choice D) is a nutrient and energy source; it does not play a role in protecting the stomach and intestine from self-digestion.

2. The hormone secretin stimulates production of a buffering solution for the duodenum by the:

• A. stomach.
• B. liver.
• C. pancreas.
• D. oxyntic cells.

Correct answer: C

Rationale: The correct answer is C: pancreas. Secretin stimulates the pancreas to release bicarbonate, which acts as a buffering solution to neutralize the acid entering the duodenum from the stomach. This process helps in maintaining the pH balance in the small intestine. Choice A, stomach, is incorrect as the stomach does not produce the buffering solution needed for the duodenum. Choice B, liver, is incorrect because secretin does not directly stimulate the liver to produce a buffering solution. Choice D, oxyntic cells, is also incorrect as these cells in the stomach are responsible for producing gastric acid, not the buffering solution needed in the duodenum.

3. The interrelated network of nerves within the gastrointestinal wall that regulates its muscular action is known as the:

• A. gastric nerve plexus.
• B. biliary nerve plexus.
• C. intramural nerve plexus.
• D. intestinal nerve plexus.

Correct answer: C

Rationale: The correct answer is C - intramural nerve plexus. This network of nerves regulates the muscular movements within the gastrointestinal wall. The gastric nerve plexus (choice A) specifically relates to the stomach, not the entire gastrointestinal tract. The biliary nerve plexus (choice B) is associated with the bile ducts and gallbladder, not the regulation of muscular action. The intestinal nerve plexus (choice D) is a general term that doesn't specifically refer to the network of nerves within the gastrointestinal wall.

4. In addition to calcium, the major minerals needed to build and maintain bone tissue include:

• A. potassium
• B. iron
• C. phosphorus
• D. fluoride

Correct answer: C

Rationale: The correct answer is C: phosphorus. Phosphorus, along with calcium, is essential for bone health and maintenance. Potassium (choice A) is important for muscle function, iron (choice B) is crucial for red blood cell production, and fluoride (choice D) helps prevent tooth decay but is not a major mineral needed for bone tissue.

5. Two amino acids are chemically joined by a:

• A. double bond.
• B. hydrogen bond.
• C. carboxyl bond.
• D. peptide bond.

Correct answer: D

Rationale: The correct answer is D, peptide bond. A peptide bond is formed through a dehydration synthesis reaction between the amine group of one amino acid and the carboxyl group of another amino acid. This bond is crucial in protein synthesis. Choices A, B, and C are incorrect. A double bond involves sharing two pairs of electrons, a hydrogen bond is a weak attraction between a hydrogen atom and an electronegative atom, and a carboxyl bond is not a common term in biochemistry.

Similar Questions