Question

The process of taking food in through the mouth is called
(a) Egestion
(b) Digestion
(c) Absorption
(d) Ingestion

Answer 1

Hint: It is the first step in the process of consuming food or any other substances. It starts off the chain of events that ultimately leads to the formation of energy from food that is eaten.

Complete answer:
The process of taking food or consuming another substance into the body by swallowing is known as ingestion. In animals, the ingestion takes place through the mouth whereas in single- celled organisms it takes place by absorbing a substance through the cell membrane. Structures in the oral cavity like teeth, tongue, salivary gland, esophagus, etc.
- Teeth help in mechanical means like tearing, shredding, grinding of food.
- Salivary glands secrete saliva which helps in the chemical breakdown of food through various enzymes.
- The tongue is a voluntary muscular and glandular structure that occupies the floor of the mouth. The main function of the tongue is taste. Tastes could be sweet, sour, bitter, and salty. This characteristic function of the tongue is due to the presence of taste buds. The tongue also helps to push the food toward the teeth to be processed.
- The teeth, tongue, and saliva together mix up the food thoroughly. Mucus in saliva helps in lubricating and adhering masticated food particles into a bolus. Saliva also contains salivary enzymes like salivary amylase which breaks down the starch to maltose. This bolus is then pushed down through the pharynx into the esophagus. This process is called swallowing or deglutition.
- This bolus passes down from the esophagus through successive muscular contraction called peristalsis reaches the stomach through the gastro- esophageal sphincter.
So, the correct answer is ‘Ingestion’.

Note:
- Ingestion is a part of the digestion of food.
- The oral cavity leads to the pharynx which is a common passage for food and air. The pharynx leads to the esophagus. Glottis is the opening for the windpipe.
- Epiglottis is a cartilaginous flap that prevents the entry of food into the windpipe during swallowing.