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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. Chief cells secrete pepsinogen, not HCl.

B. Parietal cells in the stomach lining are responsible for secreting hydrochloric acid (HCl). This acid is crucial for digestion and killing pathogens.

C. Mucous cells secrete mucus, which protects the stomach lining from the acidic environment. They do not secrete HCl.

D. Regenerative (stem) cells are involved in the renewal of the stomach lining, but they do not secrete HCl.

Correct Answer is A

Explanation

A. Y chromosome: The SRY gene on the Y chromosome codes for the testis-determining factor (TDF), which initiates the development of testes and male characteristics.

B. Gonadal ridges: The gonadal ridges are the precursor structures that develop into gonads but do not contain the gene for TDF.

C. X chromosome: The X chromosome contains genes important for development but does not code for TDF.

D. Fetal testes: The fetal testes produce testosterone but are not the source of the TDF gene.