Question 1

Which enzyme present in human saliva initiates the chemical digestion of carbohydrates?

Accepted Answer

Salivary Amylase. Salivary amylase breaks down starch into simpler sugars like maltose. This process begins in the mouth as soon as food is chewed. It requires an optimum pH of about 6.8 to function effectively.

Question 2

What is the primary role of Bile juice secreted by the liver?

Accepted Answer

Emulsification of fats. Bile juice breaks down large fat globules into smaller droplets to increase the surface area for enzymes. This process is essential for the subsequent action of lipase. Although it aids digestion, bile contains no digestive enzymes itself.

Question 3

In which part of the human digestive system does the maximum absorption of nutrients occur?

Accepted Answer

Small Intestine. The small intestine has a very large surface area due to the presence of villi. These finger-like projections facilitate the efficient transfer of nutrients into the bloodstream. It is the longest part of the alimentary canal in humans.

Question 4

Which acid is secreted by the gastric glands of the stomach to aid digestion?

Accepted Answer

Hydrochloric Acid. Hydrochloric acid provides the acidic medium necessary for the activation of pepsin. it also serves to kill harmful bacteria that may enter with food. The stomach lining is protected from this acid by a thick layer of mucus.

Question 5

The wave-like muscular contractions that push food along the digestive tract are called?

Accepted Answer

Peristalsis. Peristalsis involves the involuntary contraction and relaxation of muscles in the esophagus and intestines. This motion ensures that food moves in one direction through the system. It occurs throughout the entire length of the alimentary canal.

Digestive System — Set 1