When the sympathetic nervous system is stimulated, the ...

[jake]

When the sympathetic nervous system is stimulated, the interstitial cells of Cajal, pacemaker cells of the GI tract, react by
 
  A)
  decreasing amplitude or abolishing the slow waves that control the spontaneous oscillations in membrane potentials.
  B)
  increasing the peristaltic motion of the GI tract, thereby causing explosive diarrhea.
  C)
  increasing the amount of secretions being entered into each segment of the intestinal tract.
  D)
  signaling the vagus nerve to slow down motility and increase absorption of water from the large intestine.

Question 2

A 60-year-old man has been diagnosed with renal calculi after repeated episodes of excruciating flank pain in recent weeks.
 
  The man states that, I don't know how this could happen to me, since I'm so careful about eating a healthy diet. What is the most appropriate response to the man's statement?
  A)
  Your diet may have played a part in this, but in fact, genetics are likely primarily to blame.
  B)
  What you eat can influence your risk of stone formation, but many other factors like hormones and your metabolism are involved.
  C)
  You likely don't need to change your diet, but now that you have stones in one kidney, you're at very high risk of growing them in the other kidney.
  D)
  Your diet might be normally healthy, but high intake of normally beneficial minerals like calcium and magnesium can lead to stones.

[polinasid]

Answer to Question 1

Ans:
A

Feedback:

The interstitial cells of Cajal that are found in groups between the layers of smooth muscle tissue are hypothesized to function as the pacemakers. These cells display rhythmic, spontaneous oscillations in the membrane potentials, called slow waves, ranging in frequency from approximately 3 per minute in the stomach to 12 per minute in the duodenum. The vagus nerve responds to parasympathetic innervation. GI motility is enhanced because of increased vagal activity that could cause diarrhea.

Answer to Question 2

Ans:
B

Feedback:

Renal calculi have a complex etiology that includes diet, but also many other metabolic and endocrine factors, among others. Genetics are not identified as a contributor, and mineral intake is not likely to be the sole factor. Stone formation is normally unilateral.

[jake]

Thank you

[polinasid]

Happy to help you