Question

61-1/Which of the following substances increases gastric emptying?

Select one: _

a. Secretin

b. Cholecystokinin

c. Gastric inhibitory peptide

d. Acetylcholine

2/Polyspermy during fertilization is prevented by hardening of:

Select one:

a. zona pellucida

b. corona radiata

c. ZP3 receptors

d. acrosomal membrane

3/A patient attends emergency room because of abdominal pain. Investigations revealed normal levels of pancreatic enzymes, pepsinogen and normal stomach and gall bladder motility. pH measurements revealed acidic small intestine environment. Which of the following hormones is imbalanced?

Select one: _

a. Motilin _

b. Secretin

c. Leptin

d. Cholecystokinin

4/Damage to which of the following structures would stop breathing?

Select one:

_ a. Intercostal nerves

b. Vagus nerves

C. Medulla

d. Pons

Answer 1

61 1 d) Acetylcholine increases gastric emptying by increasing the gastric motility that is by the contraction of the gastric smooth muscles.

Cholecystokinin ,secretin and gastric inhibitory peptide inhibit gastric emptying.

2 a) Polyspermy is prevented by hardening of Zona pellucida. During fertilization , the structural changes in Zona which surround the eggs are driven by the exocytosis of cortical granules and becomes impermeable.

3.b) Secretin enters the intestinal lumen and stimulates bicarbonate secretion. So their imbalance, decreases bicarbonate and cause acidic small intestine.

Action of cholecystokinin is normal due to gall bladder motility.

Motilin action is normal due to normal stomach motility.

4. c) Medulla damage stops breathing. Out of 3 Respiratory centres, though one is located in pons, 2 centres are in medulla oblongata and it is known as the primary respiratory control centre. It sends signals to the muscles that control Respiration for Breathing to occur.