Test: Nutrition In Animals - UPSC MCQ

Tapeworm is a parasite which obtains nutrition from the body of its host. The host indirectly depends on plants for its food. Banyan tree is autotrophic. Grasshopper and rat directly depend on plants as they consume plants and plant products as food.

An anal sphincter is a group of muscles at the end of the rectum that surrounds the anus and controls the release of stool, thereby maintaining continence. There are two sphincter muscles: one is internal and one is external. The external muscle helps maintain continence and keep stool in the rectum.

The process of digestion begins in the mouth with mastication. Food passes from the mouth, through the esophagus, and into the stomach before it reaches the small intestine

Typical movement of the esophagus, stomach, and intestine are called peristalsis. The action of peristalsis looks like an ocean wave moving through the muscle

Protein digestion begins in the stomach with the action of an enzyme called pepsin. Pepsin is the active protein-digesting enzyme of the stomach

The heart beat (contraction) begins when an electrical impulse from the sinoatrial node (also called the SA node or sinus node) moves through it. The SA node is sometimes referred to as the heart's "natural pacemaker" because it initiates impulses for the heartbeat.

Oesophagus is a tube which simply conducts food from the throat to the stomach. It does not produce any digestive enzyme.

Bilirubin, an abundant bile pigment in mammalian serum, was once considered a toxic waste product and has more recently been recognized as a potent antioxidant of physiological importance. 

During digestion fats are broken down into fatty acids and glycerol by the process of emulsification of fats which is one of the main function of the bile juice secreted by the liver and stored in gall bladder

Digestion of proteins starts in stomach and is completed in intestine. The pepsin is the most important proteolytic enzyme present in stomach. It is secreted in inactive pepsinogen form which is activated on exposure to gastric acid. Pepsin breaks proteins into smaller proteoses and peptones. The peptones, proteoses are acted upon by trypsin, chymotrypsin and carboxypeptidase present in pancreatic juice. The action of these enzymes breaks peptones and proteoses into dipeptides. In intestinal juice is present aminopeptidase which finally release amino acids from dipeptides, thus finishing the digestion of proteins.