Question

The walls of the food pipe secretes a slippery substance called _____.

• A. Saliva
• B. Mucus
• C. Bolus
• D. Bile Juice

Hint:

Mucus acts as a lubricant in the digestive tract and helps food move smoothly through the oesophagus.

Answer 1

The Correct Option is B

Concept: The food pipe, also known as the oesophagus, is a muscular tube that carries food from the mouth to the stomach. To help food move smoothly through this passage, the inner walls of the food pipe secrete a slippery substance. This slippery secretion reduces friction and protects the lining of the food pipe during swallowing.

Step 1: Understanding the role of the food pipe. After food is chewed in the mouth and swallowed, it enters the oesophagus. The food needs to move smoothly toward the stomach without damaging the walls of the passage. For this purpose, the walls of the food pipe produce: \[ \boxed{\text{Mucus}} \] Mucus is a slimy and slippery substance that:
• Lubricates the food passage
• Helps easy movement of food
• Prevents friction and injury

Step 2: Analysis of the incorrect options.
• Option (1) Saliva: Saliva is secreted by salivary glands in the mouth, not by the food pipe.
• Option (3) Bolus: Bolus is the chewed mass of food formed in the mouth.
• Option (4) Bile Juice: Bile juice is produced by the liver and helps in fat digestion. Therefore, the correct answer is: \[ \boxed{(2)\ \text{Mucus}} \]