Receptors proteins are required for body's communication which are embedded in cell membranes in such a way that active site is at the outside region. 

Antiseptics are used on living organisms, such as human skin, to kill any microorganisms living on the bodies surface. Disinfectants are used on non-living things, such as countertops and handrails, to kill the microorganisms living on that inanimate surface.

Saccharin is an artificial swetening 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 month or by conc. HNO₃ in the laboratory.

Some substances are added to soap to make it more useful for particular applications. They are called fillers, e.g. sodium rosinate is added to laundry soap to increase its foaming capacity. Glycerol is added in shaving soaps to prevent them from rapid drying.

(i) A spartame decomposes at baking or cooking temperatures and hence can be used as a sweetening agent only in cold foods and drinks. 
(ii) Detergents being non-biodegradable persists in water even after sewage treatment and thus, cause foaming in river water.