Physiology of digestion -Advance Level
Dear Readers,
Compared to other sections, Zoology is considered to be the most scoring section. If prepared thoroughly, Zoology can help students to secure a position in the exam. These questions are very important in achieving your success in Exams after 12th.
Q1. The enzyme invertase hydrolyses
Invertase is an enzyme, that catalyzes the hydrolysis (breakdown) of sucrose. The resulting mixture of fructose and glucose is called inverted sugar syrup. Sucrase is also called invertase.
Q2. Milk protein is curdled into calcium paracaseinate by
In young mammals, milk protein caseinogen is digested with the help of an enzyme called rennin. Prorennin is converted into active rennin in the presence of HCl. Rennin curdles milk protein caseinogens, which is hydrolyzed into casein.
Q3. Which of the following belongs to the class of pepsin and trypsin [CPMT 1984]
Pepsin and renin are enzymes secreted by the gastric pits in the stomach. They are the active forms of pepsinogen and prorenin respectively, which activate when they come into contact with the hydrochloric acid in the stomach.
Q4. which are rich in fat are not digested in the intestine in absence of
Pancreatic lipase (formerly called stoop sin) hydrolyzes fats into glycerol and fatty acids.
Q5. Digestion of which component of the food is likely to be most adversely affected if the pH of stomach is made neutral [MP PMT 1992]
In the stomach, hydrochloric acid and pepsinogen, interact to create pepsin, an enzyme that plays a very important role in protein digestion. The process that takes place, when proteins are disintegrated by the enzymes is called hydrolysis.
Q6. Trypsin acts in a medium which is [AFMC 1985]
Trypsin is a serine protease found in the digestive system of many vertebrates, where it hydrolyzes proteins.
Q7. Peyer's patches in the intestine are the site of production of
numerous solitary lymphoid nodules spread throughout the lamina of the gut. Their main function is the production of immunoglobulin A (IgA) along with other types of immunoglobulins.
Q8. Glucose, galactose and fructose all have the same molecular size and composition and their absorption through the mucosal cells takes place
ANSWER Carbohydrates are broken down and absorbed in the form of monosaccharides. Various kinds of monosaccharides are absorbed at different rates the rate of absorption of the different sugars has been found in the following decreasing order - galactose, glucose, fructose, mannose, xylose.
Q9. Which cells secrete gastric enzymes in stomach [CPMT 1988]
A gastric chief cell (also known as a zymogenic cell or peptic cell) is a cell in the stomach that releases pepsinogen and chymosin. Alpha cell, beta cell and Islets of Langerhans are present in pancreas.
Q10. Fatty acid and glycerol are first taken up from alimentary canal by [CPMT 1984; AFMC 1994]
Generally, fatty acids upto a chain length of 10 carbon atom are primarily absorbed through the blood capillaries, but those with higher chain length through lymphatic route (lymph vessels).
