Answer:
The correct answer will be option-B.
Explanation:
Viral polymerases are the enzymes which play an important role in the viral genome transcription and replication.
Retrovirus is the single-stranded RNA viruses which replicate through a DNA intermediate and therefore requires the <em>RNA-dependent DNA polymerase or reverse transcriptase</em>. Reverse transcriptase encodes DNA from the strand of RNA which can be replicated and helps in the reproduction of the virus.
Thus, option- B is the correct answer.
A triploid cell is the structure form during angoisperm fertilization. The cell are created in the process known as double fertilization into the endosperm which is mostly are polyploid. These are typicallly triploids that is they contain three sets of chromosomes but they varies widely from diploid (2n) to 15N.
Considering the following;
I. Heat is not readily available to all living cells.
II. Heat at excessive amounts denatures proteins.
III. Heat does not provide the activation energy for their reactions.
IV. When a critical temperature is reached, proteins no longer function
Answer;
I and IV
Explanation;
Living cells cannot use heat to provide the activation energy for biochemical reactions because heat is not readily available to all living cells and also when a critical temperature is reached, proteins no longer function.
Too much heat can kill an organism by rendering its organelles, cells, tissues and organs permanently inoperable and un-salvageable. The same process can be observed in tissues at low temperatures, and is the cause of frostbite. This is because enzymes are denatured by high temperature and inactivated by low.