Which of the following heterotroph indirectly depends on autotrophs for its survival?
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.
The exit of waste materials from the human alimentary canal is regulated by:
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 in humans is completed in:
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
The muscles of the digestive tract contract and relax to allow food to move in downward direction. This process is called ________.
Typical movement of the esophagus, stomach, and intestine are called peristalsis. The action of peristalsis looks like an ocean wave moving through the muscle
Which enzyme is responsible for digesting proteins in the stomach?
Protein digestion begins in the stomach with the action of an enzyme called pepsin. Pepsin is the active protein-digesting enzyme of the stomach
Which of these initiates the heartbeat?
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.
Which of the following region of the human alimentary canal does not produce any digestive enzyme?
Oesophagus is a tube which simply conducts food from the throat to the stomach. It does not produce any digestive enzyme.
Which of the following is a bile pigment?
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 to:
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:
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.