Nokea
What is the chemical structure that forms the base component of an amino acid?
- A. carboxyl group
- B. carbon chain
- C. radicals
- D. amino group
Correct Answer: D
Rationale: The correct answer is the amino group. Amino acids consist of an amino group (NH2), a carboxyl group (COOH), a hydrogen atom, and a variable side chain attached to a central carbon atom. The amino group is essential for the formation of proteins. The carboxyl group is not the base component but another important functional group in amino acids. Carbon chain and radicals are not specific chemical structures that form the base component of an amino acid.
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Feces are composed mainly of bacteria, mucosal cells, mucus, and what else?
- A. bile
- B. enzymes
- C. fiber
- D. chyme
Correct Answer: C
Rationale: The correct answer is 'C: fiber.' Feces are primarily made up of indigestible material, such as fiber. Bile (choice A) is produced by the liver to aid in digestion but is not a major component of feces. Enzymes (choice B) are involved in digestion but are not a significant component of feces. Chyme (choice D) is the semi-fluid mass of partially digested food that moves from the stomach to the small intestine and is not a major component of feces.
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.
What is the process of converting glycogen to glucose called?
- A. Glucogenesis.
- B. Glycogenolysis.
- C. Glyconeogenesis.
- D. Gluconeogenesis.
Correct Answer: B
Rationale: The correct answer is B: Glycogenolysis. Glycogenolysis is the process of breaking down glycogen into glucose. Choices A, C, and D are incorrect. Glucogenesis (choice A) is not a term used in biochemistry. Glyconeogenesis (choice C) refers to the synthesis of new glucose molecules from non-carbohydrate sources, not the breakdown of glycogen. Gluconeogenesis (choice D) is the process of producing glucose from non-carbohydrate sources, not the breakdown of glycogen.
Which hormone prevents excessive gastric activity?
- A. Gastrin
- B. Enterogastrone
- C. Secretin
- D. Cholecystokinin
Correct Answer: B
Rationale: The correct answer is Enterogastrone. Enterogastrone is a hormone that inhibits excessive gastric activity by slowing down stomach contractions and emptying. Gastrin (choice A) stimulates gastric acid secretion, secretin (choice C) regulates pH levels in the duodenum, and cholecystokinin (choice D) stimulates the release of digestive enzymes and bile.
Why are bacteria found in the colon important?
- A. synthesize important vitamins.
- B. complete the process of absorption.
- C. synthesize some minerals.
- D. finish the process of digestion.
Correct Answer: A
Rationale: Bacteria found in the colon are important because they synthesize important vitamins, such as vitamin K. This aids in the body's overall health and functioning. Choice B is incorrect because absorption primarily occurs in the small intestine, not the colon. Choice C is incorrect as the synthesis of minerals is not a primary function of colon bacteria. Choice D is incorrect as the digestion process mainly occurs in the stomach and small intestine.