Question

Pyloric sphincter guards the opening between
A. Stomach and duodenum
B. Cardio and fundus
C. Esophagus and stomach
D. Fundus and pylorus

Answer 1

Hint: Pyloric sphincter is named after the part of the organ it is attached to. Sphincters prevent the backflow of food to the previous organ.

Complete Answer:
The stomach is a hollow organ situated just below the diaphragm on the left side in the abdominal cavity. The stomach has two curvatures. One on the right side is lesser curvature and the other on the left side is greater curvature.

In humans, the stomach has four parts:
1. Cardiac region
2. Fundus
3. Body or corpus
4. Pyloric region

1. Cardiac Region: Cardiac region is the upper part of the stomach where the esophagus opens. This portion is also known as the cardiac end.
2. Fundus: Fundus is a small dome shaped structure. It is elevated above the level of the esophageal opening.
3. Body: The body is the largest part of the stomach forming about 75% to 80% of the whole stomach. It extends from below the fundus to the pyloric region.
  4. Pyloric Region: Pyloric region has two parts, antrum, and pyloric canal. The body of the stomach ends in the antrum.
- The junction between body and antrum is marked by an angular notch. The antrum is continued as the narrow canal, which is called the pyloric canal or pyloric end.
- The pyloric canal opens into the first part of the small intestine called the duodenum. The opening of the pyloric canal is guarded by a sphincter called the pyloric sphincter. It opens towards the duodenum.
- Sphincters prevent the backflow of food from the duodenum to the stomach.

So, the answer is A stomach and duodenum.

Note: There is one more sphincter related to the stomach. The cardiac sphincter is between the esophagus and the cardiac part of the stomach. It prevents the backflow of food from the stomach to the esophagus. This sphincter opens only towards the stomach.