Question

Q1. Which of the following spontaeosly depolarizes to cause slow waves of contraciton throughout the intestines?

A. Interstial cells of cajal

B. Sensory afferent intrinsic neurons

C. Interneurons

D. Motor efferent intrinsic neurons

Q2. Which of the following is true?

A. Brush border peptidases finish the digestion of proteins

B. Brush border enzymes are found in the precursoe form and must be activated

C. Brush border enxymes are secreted into the lumen of the small intestines

Q3. Old RBC (Red blood cells) are removed from circulation by the spleen. They are broken down and removed heme (minus iron) forms which of the following?

A. Bilirubin

B. Micelles

C. Bile acids

D. Urobilinogen

Answer 1

1.A interstitial cells of cajal

Origin of slow wavesoa occur at interstitial cells of Cajal slow waves occur spontaneously.

2. A. Brush border peptidases finish the digestion of proteins

The final stage of protein digestion occurs on the brush border of the small intestine epithelium. membrane-bound peptidases complete digestion of oligopeptides to either single amino acids or dipeptides and tripeptides.

3. A. Bilirubin

The break down products are recycled or removed as wastes:

Globin is broken down into amino acids for synthesis of new proteins.

iron is stored in the liver or spleen or used by the bone marrow for production of new erythrocytes, and the remnants of heme are converted into bilirubin