Question

Which of the following is used as a preservative for biological specimens?
A. Acetic acid
B. Chloroform
C. Formalin
D. Formic acid

Answer 1

Hint:Preservatives are those substances which are used for preserving things from damages like, food, biological specimens, etc. The food is preserved from spoilage caused by fungus, bacteria, etc. The preservatives are added in many things just to protect from the growth of microorganisms. The preservative used in food products is strictly regulated, studied and monitored by FDA (Food and Drug Administration).


Complete step by step solution:
Preservatives are used to preserve the substances. In the same manner, to prevent biological specimens the preservative is used. These are used to prevent the damages of the specimens. Formalin is one the known and famous preservative which is used for the preservation of biological specimens.
Preservatives in food: These are used to prevent molds, bacteria, fungus, yeast, etc. Preservatives can keep the food for longer and fresher for a long time. It also extends the shelf life of food. This delays the rancidity.
Preservatives in medicine: These are used in medicines commonly such as, acetaminophen, cough syrup and insulin to prevent the contamination from microbial activity.
Preservatives in wood: These are used to build road signs, telephone poles, marine pilings, decks, etc.
Preservatives in cosmetics and personal care products: These help in preventing contamination and growth from harmful bacteria in products from lotions, shampoos, foundations, sunscreens, etc.
So, the answer is formalin.

Therefore, the correct option is C. Formalin.


Note:Formalin is \[30{\text{ }} - {\text{ }}40\% \] of water in formaldehyde. The formalin is a tissue hardener and it is also used in strong disinfectant for preserving the biological and anatomical specimens. It is a pungent gas which contains the chemical formula \[HCHO\] . It's used as an antiseptic, disinfectant.