Why are certain drugs called enzyme inhibitors?
Enzymes have active sites that bind the substrate for effective and quick chemical reaction. The functional groups present at the active site of enzyme react with functional groups of substrate via .ionic bonding, van der Waals' interaction, etc. Some drugs interfere with this interaction by blocking the binding site of enzyme and also prevent the binding of actual substrate with enzyme. This inhibits the catalytic activity of the enzyme. Therefore, these are called inhibitors.
Assertion (A): Receptor proteins show selectivity for one chemical messenger over the other.
Reason (R): Chemical messenger binds to the receptor site and inhibits its natural function.
Between sodium hydrogen carbonate and magnesium hydroxide which is a better antacid and why?
While antacids and antiallergic drugs interfere with the function of histamines, why do these not interfere with the function of each other?
Assertion (A): Artificial sweeteners are added to the food to control the intake of calories.
Reason (R): Most of the artificial sweeteners are inert and do not metabolise in the body.
Aspirin is pain relieving antipyretic drug but can be used to prevent heart attack. Explain.
Which of the following are sulpha drugs?
(a) Sulphapyridine (b) Prontosil
(c) Salvarsan (d) Nardil
Which of the following are antidepressants?
(a) Iproniazid (b) Phenelzine (c) Equanil (d) Salvarsan
What is the advantage of using antihistamines over antacids in the treatment of acidity?
Sodium salts of some acids are Very useful as food preservatives. Suggest a few such acids.
Assertion (A): Chemical messenger gives message to the cell without entering the cell.
Reason (R): Chemical messenger is received at the binding site of receptor proteins.
What are enzyme inhibitors? Classify them on the basis of their mode of attachments on the active site of enzymes. With the help of diagrams explain how do inhibitors inhibit the enzymatic activity.
Ckemistnj in Evenjdai] Life 325
With refrence to which classification has the statement "ranitidine is an antacid", been given?
What happens when the bond formed between an enzyme and an inhibitor is a strong covalent bond?
Which of the following statements are incorrect about receptor proteins?
(a) Majority of receptor proteins are embedded in the cell membranes.
(b) The active site of receptor proteins opens on the inside region of the cell.
(c) Chemical messengers are received at the binding sites of receptor proteins.
(d) Shape of receptor does not change during attachment of messenger.
Which of the following statements are correct about barbiturates?
(a) Hypnotics or sleep producing agents.
(b) These are tranquilizers.
(c) Non-narcotic analgesics.
(d) Pain reducing without disturbing the nervous system.
Assertion (A): Sulpha drug contain sulphonamide group.
Reason (R): Salvarsan is a sulpha drug.
Assertion (A): Competitive inhibitors compete with natural substrate for their attachment on the active sites of enzymes.
Reason (R): In competitive inhibition, inhibitor binds to the allosteric site of the enzyme.
Assertion (A): All chemicals added to food items are called food preservatives.
Reason (R): All these chemicals increase the nutritive value of the food.
Assertion (A): Preservative are added to food items.
Reason (R): Preservatives inhibit the growth of microorganisms.
With refrence to which classification has the statement "ranitidine is an antacid", been given?
Compounds with antiseptic properties are
(a) CHCl, (b) CHI3
(c) Boric acid (d) 0.3 ppm aqueous solution of Cl2
Both antacids and antiallergic drugs are antihistamines but they cannot replace each other. Explain why?