Question

Gastro-colic reflex means
A. Expulsion of bacteria from gut
B. Removal of faeces
C. Amino Acid synthesis
D. Both B and C

Answer 1

When food arrives into the stomach, the body releases a hormone that causes the colon to contract. These contractions drive the previously consumed food deeper into the digestive system, which may contribute to an impulse to expel the stool.

Complete Answer:
- The gastrocolic reflex is a natural spontaneous reaction to food entering the stomach. As a consequence of the gastrocolic reflex, the motility of the colon increases in response to the stretching of the stomach with the intake of food.
- The gastrocolic reflex makes space for the intake of more food by regulating the peristalsis and pushing the food consumed distally into the rectum. It is this reflex that leads many people to have an urge to defecate within an hour or so of consuming a full meal.
- Sigmoid colon is the area most affected by the phasic reaction of digestion, which consists of cyclical cycles of contraction accompanied by relaxation in order to propel food distally into the rectum. These contractions are produced in the myenteric plexus and performed by the external muscularis.
- When food reaches the rectum and causes pressure to increase, the gastrocolic reflex triggers the defecation of the content of the rectum. Thus gastrocolic reflex results in the tendency to defecate after a meal.

Thus the correct answer is option B i.e., Removal of faeces.

Note: Certain health problems can have an effect on the gastrocolic reflex. For example Irritable Bowel Syndrome (IBS) may force the digestive tract to pass food through the system even faster than normal.