A source of roughage in the human diet is supplied by certain

Answer Explanation

C) absorbed food is the raw material for metabolism

- Correct: The digestion of food and subsequent absorption into the bloodstream are essential processes because absorbed food molecules serve as the raw material for metabolism. Once nutrients from food are absorbed into the bloodstream, they are transported to cells throughout the body where they are used for various metabolic processes. Carbohydrates are broken down into glucose, which is used for energy production. Proteins are broken down into amino acids, which are used for building and repairing tissues, as well as for synthesizing enzymes and hormones. Fats are broken down into fatty acids and glycerol, which are used for energy production and for building cell membranes and certain hormones. Overall, absorbed food molecules provide the necessary energy and building blocks for cellular activities, growth, and maintenance of the body.

A) absorbed food is toxic to the body

- Incorrect: Absorbed food is not inherently toxic to the body. In fact, nutrients obtained from food are essential for the body's survival and proper functioning. However, certain substances in food may be harmful if absorbed in excessive amounts, such as certain vitamins or minerals. Generally, the body has mechanisms to regulate nutrient absorption and maintain homeostasis.

B) absorbed food stimulates reproduction

- Incorrect: While proper nutrition is important for overall health and fertility, absorbed food does not directly stimulate reproduction. Reproduction is regulated by various hormones and physiological processes within the body.

D) absorbed food aids in respiration

- Incorrect: While nutrients obtained from food are used by cells for energy production through respiration, absorbed food itself does not directly aid in respiration. Respiration is a complex physiological process that involves the exchange of gases (oxygen and carbon dioxide) in the lungs and cellular respiration within cells to produce energy.

Answer Explanation

A) Mouth, Esophagus, Stomach: This option is incorrect because while saliva in the mouth does contain digestive enzymes (such as amylase for breaking down carbohydrates), the esophagus is not a site of enzyme secretion. The stomach secretes gastric juices which primarily contain hydrochloric acid and pepsinogen (which is converted to pepsin, a protein-digesting enzyme), but the esophagus itself does not secrete digestive enzymes.

B) Stomach, Small Intestine, Large Intestine: This option is incorrect because while both the small intestine and the large intestine play crucial roles in digestion and absorption, enzyme secretion mainly occurs in the stomach and small intestine. The large intestine primarily absorbs water and salts and does not secrete digestive enzymes.

C) Mouth, Stomach, Small Intestine: This option is correct. Enzymes are secreted in the mouth (amylase), stomach (pepsin for protein digestion), and small intestine (various enzymes including pancreatic enzymes like lipase, protease, and amylase, as well as enzymes produced by the intestinal lining).

D) Esophagus, Stomach, Large Intestine: This option is incorrect because while the stomach does secrete digestive enzymes, the esophagus and large intestine do not. The large intestine primarily absorbs water and salts and does not secrete digestive enzymes.

Answer Explanation

Protease enzymes are responsible for breaking down proteins in our food into amino acids. Then different enzymes join amino acids together to form new proteins needed by the body for growth and repair. Protease enzymes are produced in pancreas.