Molecular Basis of Inheritance — Important Questions

Nitrogenous base, Pentose sugar, Phosphate group

A nucleotide consists of three components: a nitrogenous base (purine or pyrimidine), a pentose sugar (ribose in RNA or deoxyribose in DNA), and a phosphate group. Amino acids are components of proteins, and fatty acids are components of lipids.

It is semiconservative, Both strands serve as templates, It requires DNA polymerase, It produces identical copies

DNA replication is semiconservative (each new DNA has one old and one new strand), uses both strands as templates, requires DNA polymerase enzyme, and produces identical copies. In eukaryotes, replication occurs in the nucleus, not cytoplasm.

DNA ligase

DNA ligase joins the discontinuously synthesized DNA fragments (Okazaki fragments) on the lagging strand during replication. DNA polymerase synthesizes DNA, RNA polymerase makes RNA, and helicase unwinds DNA.

UAA, UAG, UGA

UAA, UAG, and UGA are the three stop codons that signal the termination of protein synthesis. AUG is the start codon that codes for methionine, and UUU codes for phenylalanine.