Genetic Engineering and Biotechnology

Storage of biological tissues such as blood, organs, semen requires low temperature which is achieved upon the usage of

[amp_mcq option1=”Liquid nitrogen” option2=”Solid carbon dioxide” option3=”Liquid air” option4=”Helium” correct=”option1″]

Storage of biological tissues such as blood, organs, and semen at very low temperatures (cryopreservation) is typically achieved using Liquid nitrogen.

– Liquid nitrogen has a boiling point of -196°C (-320°F).
– This extremely low temperature freezes biological samples and halts cellular activity and degradation.
– Cryopreservation methods often involve cooling biological material to liquid nitrogen temperatures for long-term storage.

Solid carbon dioxide (dry ice) provides a temperature of -78.5°C, which is not sufficiently low for long-term cryopreservation of most biological tissues. Liquid air and helium are less commonly used than liquid nitrogen for standard biological sample storage due to cost, availability, or specific temperature requirements.

Consider the following pairs of vaccine and category/type:

• 1. Covaxin : Inactivated pathogen-based vaccine
• 2. Covishield : mRNA vaccine
• 3. Sputnik V : Viral vector-based vaccine

Which of the pairs given above is/are correctly matched ?

[amp_mcq option1=”1 only” option2=”2 and 3 only” option3=”1 and 3 only” option4=”1, 2 and 3″ correct=”option3″]

Pairs 1 and 3 are correctly matched regarding the vaccine type, while pair 2 is incorrect.

– Covaxin, developed by Bharat Biotech in India, is an inactivated vaccine. It uses a killed version of the SARS-CoV-2 virus to trigger an immune response.
– Covishield, manufactured by Serum Institute of India, is a viral vector vaccine. It uses a modified adenovirus (a common cold virus) to deliver genetic material of the SARS-CoV-2 spike protein into cells, prompting an immune response. It is not an mRNA vaccine.
– Sputnik V, developed by the Gamaleya Research Institute in Russia, is also a viral vector vaccine, using two different adenoviruses (Ad26 and Ad5) for the two doses.

– mRNA vaccines (like Pfizer-BioNTech and Moderna) use messenger RNA to instruct cells to make a piece of the virus’s spike protein, triggering an immune response.
– Viral vector vaccines (like AstraZeneca/Covishield, Sputnik V, and Johnson & Johnson) use a harmless virus to deliver genetic instructions for making the spike protein.
– Inactivated vaccines (like Covaxin, Sinovac, Sinopharm) use killed viral particles.

Genetically modified (GM) crops contain modified genetic material due to :

• introduction of new DNA
• removal of existing DNA
• introduction of RNA
• introduction of new traits

Select the correct answer using the code given below:

[amp_mcq option1=”1 and 2 only” option2=”1, 2 and 3″ option3=”3 and 4″ option4=”1, 2 and 4″ correct=”option1″]

Genetically modified (GM) crops are created by altering the genetic material (DNA) of a plant. This modification is achieved through various techniques, most commonly by introducing new DNA sequences (transgenes) that confer desired traits (e.g., insect resistance, herbicide tolerance). Modification can also involve altering or removing existing DNA sequences using gene editing tools. Therefore, the introduction of new DNA and the removal of existing DNA are direct causes of modified genetic material in GM crops. Introduction of RNA (statement 3) is not the primary method for creating stable genetic modification in the genome, although RNA interference techniques derived from GM methods can use RNA to regulate gene expression. Introduction of new traits (statement 4) is the intended outcome or result of the genetic modification, not the cause of the modification itself. Hence, the modification is primarily due to the introduction of new DNA and/or removal/alteration of existing DNA.

Genetic modification involves making changes to the organism’s DNA, which can include adding new DNA or altering/removing existing DNA.

Other genetic modification techniques include targeted mutagenesis, gene editing (like CRISPR-Cas9), and cisgenesis (introduction of genes from the same species). The core principle remains the alteration of the organism’s genetic material (DNA).