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Carbohydrate digestion begins in the____________ whereas protein digestion begins in the ___________.

A.

liver; small intestine

B.

mouth; stomach

C.

small intestine; stomach

D.

mouth; small intestine

Answer and Explanation

The Correct Answer is B

A. Liver; small intestine: Carbohydrate and protein digestion do not begin in the liver or the small intestine. The liver is involved in metabolism but not in the initial digestion of carbohydrates or proteins. 

 

B. Mouth; stomach: Carbohydrate digestion begins in the mouth with salivary amylase, while protein digestion begins in the stomach with pepsin.

 

C. Small intestine; stomach: Carbohydrate digestion begins in the mouth and not the small intestine. Protein digestion starts in the stomach, not the small intestine. 

 

D. Mouth; small intestine: Carbohydrate digestion begins in the mouth, but protein digestion begins in the stomach, not the small intestine.


View Related questions

Correct Answer is B

Explanation

A. 20,000 to 30,000: This number is too high for the typical number of sperm that reach the vicinity of the egg.

B. 20 to 200: This number is within the range of the actual number of sperm that typically reach the vicinity of the egg.

C. Half: This is an exaggerated number, as far fewer than half of the ejaculated sperm reach the vicinity of the egg.

D. 2000 to 3000: This number is too high for the typical number of sperm that reach the vicinity of the egg.

Correct Answer is C

Explanation

A. Lactateis produced during anaerobic metabolism (when oxygen is scarce) as a byproduct of glycolysis, but it is not the direct product of glycolysis itself.

B. Carbon dioxideis a byproduct of cellular respiration, specifically during the Krebs cycle, not glycolysis.

C. Pyruvateis the end product of glycolysis, where glucose is broken down into two molecules of pyruvate.

D. Acetyl-CoAis formed from pyruvate during the transition step before the Krebs cycle, not directly from glycolysis.