Which of following is not considered an accessory organ of the digestive system?
A. liver
B. salivary glands
C. small intestines
D. pancreas
E. gallbladder
The correct answer and explanation is :
The correct answer is: C. small intestines
Explanation:
The digestive system consists of the alimentary canal (or gastrointestinal tract) and accessory organs that aid in digestion. The alimentary canal is a continuous tube through which food travels and is digested and absorbed. Accessory organs, on the other hand, are not part of this tube but contribute essential substances that facilitate digestion.
Alimentary Canal vs. Accessory Organs:
- Alimentary Canal includes:
Mouth → Pharynx → Esophagus → Stomach → Small Intestine → Large Intestine → Anus
These organs are directly involved in the movement and processing of food. - Accessory Organs include:
- Liver – produces bile to help break down fats.
- Gallbladder – stores and releases bile into the small intestine.
- Pancreas – secretes digestive enzymes and bicarbonate to neutralize stomach acid.
- Salivary Glands – secrete saliva containing enzymes like amylase, which begin carbohydrate digestion in the mouth.
These accessory organs do not directly handle food, but they secrete substances essential for digestion.
Why the Small Intestine is Not an Accessory Organ:
The small intestine is part of the alimentary canal and is the primary site for digestion and nutrient absorption. Food passes directly through it, and it plays an active role in both mechanical and chemical digestion. Therefore, it is not an accessory organ.
Conclusion:
While the liver, gallbladder, pancreas, and salivary glands assist digestion by producing or storing important digestive secretions, the small intestine is a main organ of the digestive tract. Thus, the correct answer is C. small intestines, as it is not considered an accessory organ.
