Question

Stirred-tank bioreactors have advantages over shake flasks because they……………..
(a)Provide high temperature and PH.
(b)Provide better aeration and mixing properties
(c)Do not allow the entry of $CO_2$
(d)Are easy to operate

Answer 1

Hint: The reactors which are mostly employed for culturing biological agents like cell enzymes or antibodies are known as stirred tank bioreactors (STBRs). In this bioreactor mixing among phases is generally obtained by internal mechanical agitation.

Complete answer:
-The agitator or the impeller is the main component of the stirred tank bioreactor, which mostly performs a huge range of functions such as transfer of heat and mass, aeration, and mixing for homogenization.
-The axial and the radial flow impellers are the two types of impellers that are mostly used in the conventional fermentation industry.
-For the smaller-scale production of biotechnology products the Shake flask method is used in the laboratory whereas, for large-scale production of biotechnological products, a stirred tank bioreactors are used.
-There are many advantages of Stirred tank bioreactors over shake flask-
(1)The stirred tank bioreactor provides better aeration and mixing properties.
(2)For sampling or testing a small volume of culture can be taken out of the reactors.
(3)For regulating the form it also has a form beaker.
(4)It also has a system known as a control system that regulates the temperature and pH

Additional Information: -The air is added with a device known as sparger to the culture medium under the high pressure in Stirred tank bioreactors or in short stirred tank reactors (STRs).
-The sparger is a ring-like structure consisting of many holes or tubes and along with agitators, it allows a better gas distribution system throughout the vessel.
-Sparger generates the bubbles which are broken down by impellers and dispersed throughout the medium.
-This allows the production of a uniform and homogeneous environment throughout the bioreactor
So, the correct answer is,” Provide better aeration and mixing properties”.

Note: -A vessel in which a biological reaction is the changes in the biological products that takes place is known as a bioreactor.
-Enzymes, microorganisms, animal cells, plant cells, and tissue all are involved in a biological system.
-It provides an efficient gas transfer to the growing cells. It also provides good mixing of the content and flexible operating condition.