Why are certain drugs called enzyme inhibitors?
Some drugs can block the binding site of the enzyme and prevent the binding of the substrate, or can inhibit the catalytic activity of the enzyme. Such drugs are called enzyme inhibitors.
What are fillers and what role these fillers play in soap?
Substances which are added to soaps to change their properties in order to make them more useful for a particular application, are called fillers. Some important examples are given below
(i) Sodium rosinate, sodium silicate, borax and sodium carbonate are added to laundry soaps to increase their lather forming ability.
(ii) Glycerol is added to shaving soaps to prevent them from rapid drying.
(iii) In medicated soaps, substances of medicinal values are added.
Sugar is the main source of energy as it produces energy on metabolic decomposition. But these days low calorie drinks are more popular, why?
Natural sweetners e.g., sucrose add to calorie intake. Due to occurrence of more cases of diabetes and obesity among young and old people, these days people usually take low calorie drinks. These are artificial sweetening agents as given below
Saccharin It is 550 times as sweet as cane sugar. It is excreted from the body through urine.
Aspartame It is 100 times as sweet as cane sugar. Its use is limited to cold foods and soft drinks because it is unstable at cooking temperature.
Alitame It is more stable than aspartame but the control of sweeteners of food is difficult while using it.
Sucralose It is stable at cooking temperature. It does not provide calories.
These artificial sweetening agents do not metabolize and hence do not produce any energy.
Pickles have a long shelf life and do not get spoiled for months, why?
Plenty of salt and cover of oil act as preservatives. These food preservatiues prevent spoilage of food due to microbial growth. Salt and oil do not allow moisture and air to enter the material and hence bacteria cannot thrive on them. Therefore, pickles do not get spoiled for months together.
What is the difference between saccharin and saccharic acid?
Saccharin is an artificial sweetening agent. It is about 550 times as sweet as cane sugar. It is excreted from the body in urine unchanged. It appears to be entirely inert and harmless when taken. Its use is of great value to diabetic people who need to control intake of calories.
On the other hand, saccharic acid, is a dibasic acid obtained by the bacterial oxidation of glucose in the mouth or by conc. $\mathrm{HNO}_3$ in the laboratory.
