Ribonükleotids

Ribonükleotids are the monomeric units that make up ribonucleic acid, or RNA. Each ribonükleotid consists of three components: a ribose sugar, a phosphate group, and a nitrogenous base. The ribose sugar is a five-carbon sugar. The phosphate group is attached to the 5' carbon of the ribose sugar. The nitrogenous base is attached to the 1' carbon of the ribose sugar. There are four types of nitrogenous bases found in RNA: adenine (A), guanine (G), cytosine (C), and uracil (U). Adenine and guanine are purines, while cytosine and uracil are pyrimidines.

These ribonükleotids are linked together by phosphodiester bonds to form a polynucleotide chain. The phosphate group of one ribonükleotid forms a bond with the 3' carbon of the ribose sugar of the next ribonükleotid. This creates the sugar-phosphate backbone of the RNA molecule. The sequence of nitrogenous bases along this backbone carries the genetic information. RNA plays crucial roles in gene expression, including messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA), each with specific functions in protein synthesis and cellular regulation. The structure and function of RNA are fundamental to molecular biology.