A drug that has sedatative effect is called a _________.

A substance used to relieve pain is called __________.

Detergrent molecules associated with ___________ hydrocarbon tail is a source of pollution.

Describe the following with suitable examples:
(i) Preservative                  
(ii) Artificial sweeteners
(iii) Antioxidants                
(iv) Edible colours.

Describe the following with suitable examples:
(i) Tranquilizers.
(ii) Antifertility drugs.
(iii) Antihistamines.

Explain the considerations in drug designing. 

_____________ is used as an antiseptic and disinfectant.

Explain what do you understand by spectrum of antibiotics. Give examples.