Write any two chemical differences between DNA and RNA

Feature DNA RNA Structure and location DNA usually exists in a double-stranded form and is found primarily inside the nucleus of eukaryotic cells. RNA predominantly exists in the single-stranded form and is found mostly in the cytoplasm. Feature DNA RNA Composition Its monomeric unit is called a nucleotide, which consists of deoxyribose sugar. The sugar present in its monomeric form is ribose sugar.

What are the components of nucleotides?

A phosphate group, a 5-carbon sugar, and a nitrogenous base are the three components of a nucleotide. Adenine, cytosine, guanine, and thymine are the four nitrogenous bases in DNA. Instead of thymine, uracil is contained in RNA. The genetic material of all known living organisms is made up of nucleotides in a series.

Write the important features of genetic code.

The genetic code is a set of instructions that direct the translation of DNA into 20 amino acids, the basic units of proteins in living cells. The four bases of DNA i.e., A, T, G, C combine in a way that the ribosome can read them and turn them into a protein. In the genetic code, every three nucleotides code for a single amino acid. Har Gobind Khorana received the Nobel Prize in 1968 for discoveries related to the genetic code and its function in protein synthesis. The genetic code is made up of codons. The salient features of genetic code are as follows: 1. Codon is a triplet. Out of 64 codons, 61 code for 20 amino acids and 3 codons (UAA, UGA and UAG) do not code for any amino acids. Thus, they function as terminating or stop codons. 2. Genetic code is unambiguous and specific. Thus, one codon codes for only one amino acid. 3. Some amino acids are coded by more than one codon. Hence, the code is degenerate. 4. The codon is read in mRNA in a contiguous fashion, i.e. ,without punctuation. Thus, the code is commaless. 5. The genetic code is nearly universal, i.e., particular codon codes for the same amino acid in all organisms except in mitochondria and few protozoans. 6. AUG is a codon with dual functions. It codes for the amino acid methionine (Met) and also acts as an initiator codon.

The proportion of nucleotides in a given nucleic acid are adenine: 18%, guanine: 30%, cytosine: 42% and uracil: 10%. Name the nucleic acid and mention the number of strands in it.

Nucleic acids are the important macromolecules in the cell. RNA and DNA are the major types of nucleic acid. In the given nucleic acid contain adenine, guanine, cytosine and uracil as nitrogen bases. Since it contains uracil, it is classified as a ribonucleic acid (RNA). Only the RNA contains uracil. The nucleic acid would be single-stranded since it is RNA. In many of its biological functions, RNA is a single-stranded molecule with a much shorter chain of nucleotides than double-stranded DNA. As a consequence, the nucleic acid is single-stranded and is called RNA.

What are the components of a nucleotide?

A phosphate group, a 5-carbon sugar, and a nitrogenous base are the three components of a nucleotide. Adenine, cytosine, guanine, and thymine are the four nitrogenous bases in DNA. Instead of thymine, uracil is contained in RNA. The genetic material of all known living organisms is made up of nucleotides in a series.