Question

Sterilization of tissue culture medium is done by
a. Autoclaving of medium at 120°C for 15 minutes
b. Filtering the medium through fine sieve
c. Mixing the medium with antifungal agents
d. Keeping the medium in -20°C

Answer 1

Hint: Sterilization is very important to kill all forms of microorganisms including the bacteria and fungi. Any type of contamination can be prevented when proper sterilization is done using sequential steps. Hence the further experiments can be carried out with ease and without the interference of microorganisms.

Complete answer:
Sterilization is a process mainly used to kill all forms/kinds of microbes and its spores. This process is used to maintain a sterile environment. It is usually done through combinations of several factors like heat, irradiation, filtration, high pressure, etc. Sterilization techniques are designed and used to kill or remove a wide range of all kinds of microbes including protozoa, fungi, bacteria, viruses. Mostly Autoclaving, dry heat sterilization, and filtration are used for most cell and organ culture materials.

> Autoclaving of the medium at 120°C for 15 minutes - Sterilization of the tissue culture medium is done through autoclaving at 120°C for 15 minutes. In this method, moist heat or condensed hot air is used to kill microorganisms.

> Filtering the medium through a fine sieve – this cannot make the culture sterilize.

> Mixing the medium with antifungal agents- it cannot make the culture sterile.

> Keeping the medium at -20°C – it is also the wrong option.

Hence, the correct answer is option (B).

Additional information:
The various advantages of the tissue culture technique are listed below:
- The plantlets are obtained in a very short amount of time with a small amount of plant tissue.
- The new plants produced are disease-free.
- The plants can be grown throughout the year, which does not concern the season.
- The tissue culture technique does not require a huge place to grow plants.
- Marketplace the new varieties are available easily due to the high production rate.

Note: Sterilization techniques can be easily performed and are fast enough and saves time. Sterilization can be done by providing heat, through UV radiation, by using antibiotics or by freeze drying methods.