Question

1. What is meant by redundancy or robustness of the genetic code?

2 Describe the main difference between the genome replication step during the life cycle of an RNA virus like influenza and a retrovirus like HIV, as both viruses are RNA viruses.

Answer 1

Answer1) Redundancy of the genetic code i.e. it is also known aas degenerate, however each codon specifies for single amino acids but single amino acids may have multiple codons, examples such as tryptophan.methionine each of them have multiple codons.

Answer 2) The main difference in the genome repication step during life cycle of influenza and HIV are:-

During influenza (a) The influenza virus gets attached to the epithelial cell (target) (b) Cell further engulfs the virus by endocytosis (c) Thereby, viral contents are relaeased and RNA enters the nucleus and it is replicated by RNA polymerase (d) Viral mRNA is used to prepare protein (e) New viral particles are made and released to extracellular fluids and the cell which is not killed in this further makes new virus

During HIV (a) HIV binds to the the surface receptors CD4, this process is known as attachment (b) HIV envelope and CD4 cell memrane fuss together and this step is known as Fusion and allows the entry of HIV to new cell (c) Inside the cell, HIV utilizes reverse transcriptase enzyme and converts HIV RNA to HIV DNA and thereby allows HIV to enters CD4 cell nucleus and combines with cell DNA (d) Thereby new proteins (HIV)and RNA moves to the surface and assemble to immature HIV (e) Immatur HIV pushes out of CD4 cell and releases enzyme protease, this enzyme helps in breaking long chain of immature virus and smaller immature proteins combine to form mature virus.