In this article we will discuss about the the structure of larger and smaller subunits of ribosomes. Ribosomes are ribonucleoprotein particles present in all types of cells. They were first observed in EM by Claude in the cytoplasm of cells, and later on the surface of endoplasmic reticulum by Porter and Palade. Ribosomes occur in 3 sizes: 70S in bacteria [...]
In this article we will discuss about the meaning of tRNA. The genetic message contained in the nucleotide sequence of transcribed RNA cannot be read off directly by the amino acids in the polypeptide chain. Crick and Hoagland were first to postulate that an intermediate RNA molecule functions as an "adaptor" into which the amino acid is plugged so that [...]
In this article we will discuss about the structure of RNA. RNA is a long un-branched polynucleotide chain chemically similar to DNA except for two major differences. The sugar in DNA is a deoxyribose, in RNA a ribose. Out of the 4 nucleotides, three (G, C and A) are identical in DNA and RNA. The fourth is thymine in DNA, [...]