Digestion and Absorption Test - 39

• The stomach is made of  4 layers. They are serosa, muscularis, submucosa, mucosa. These layers of smooth muscle consist of the outer longitudinal, the middle circular, and the inner oblique muscles.
• The innermost layer or lining (mucosa) contains the glands that release digestive juices which includes pepsin, chymotrypsin, hydrochloric acid etc. Hence, The inner layer of the stomach releases digestive juices.

• Nutrients are classified into five main categories: Carbohydrates, Proteins, Fats, Minerals and Vitamins.
• Carbohydrates, proteins and fats are required in large quantities in the body, and are called Macronutrients
• Minerals and vitamins are required in minute quantities in the body, and are called micronutrients.
• Thus, Option D is correct.

Solution

Correct answer is option C.

Explanation for correct option:

• Peristalsis is a series of wave-like muscle contractions that moves food to different processing stations in digestive tract. 
• The process of peristalsis starts in oesophagus when a bolus food is swallowed.
• Peristaltic movement is the movement that refers to the constriction and relaxation of muscles of the oesophagus, intestine, and stomach.

 

Chymotrypsin is an enzyme of the hydrolase class that decomposes proteins and peptides. Chymotrypsin helps in the decomposition of food proteins in the small intestine. It is synthesized by the cells of the pancreas in the form of the proenzyme chymotrypsinogen, which is converted under the action of trypsin in the intestine into active chymotrypsin. Chymotrypsin is a proteinase in the pancreatic juice that clots milk and hydrolyzes casein and gelatin. Rennin, also called chymosin, is a protein-digesting enzyme that curdles milk by transforming caseinogen into insoluble casein; it is found only in the fourth stomach of cud-chewing animals, such as cows and young infants. Rennin is absent in adults.

• Most of the digestion occurs in the first part of the small intestine while the absorption of broken down nutrients, water, vitamins, and minerals occurs in the rest of the part of intestine. 
• Once nutrients are absorbed by the intestine, they pass into the blood stream and are carried to the liver. Hence, Digested food after absorption comes into the blood.

• Nutrition refers to how an organism consumes food and how the body processes it.
• Nutrition is the process by which the organisms synthesize or obtain their own food into simpler substances so that it can be absorbed and utilized by cells of the body is called nutrition.
• Nutrients allow living organisms to develop their bodies, grow, heal damaged body parts, and supply the energy needed to carry out life processes.
• So, the correct answer is option A.