Group the following as nitrogenous bases and nucleosides:
Adenine, Cytidine, Thymine, Guanosine, Uracil and Cytosine.

Depending upon the chemical nature of the template (DNA or RNA) and the nature of nucleic acids synthesised from it (DNA or RNA), list the types of nucleic acid polymerases.

List two essential roles of ribosome during translation.

Name the scientist who suggested that the genetic code should be made of a combination of three nucleotides.

Explain the basis on which he arrived at this conclusion.

Explain the process of DNA replication with the help of a schematic diagram.

In which phase of the cell cycle does replication occur in Eukaryotes? What would happen if cell-division is not followed after DNA replication?

Name the transcriptionally active region of chromatin in a nucleus.

A DNA segment has a total of 1000 nucleotides, out of which 240 of them are adenine containing nucleotides. How many pyrimidine bases this DNA segment possesses?

120.

Draw a diagrammatic sketch of a portion of DNA segment to support your answer.