Question

What is the chemical composition of a chromosome?

one-two sentence answers, please.

Answer 1

Chromosome - it is thread like structure presents inside the nucleus of almost all cells . It is the carrier of genetic materials in the forms of gene.

Chemically, chromosomes consists of protein and nuclic acids. chromosome consists of approximately 30-40% DNA 50-60% protein and 0.5-10% RNA

Proteins of chromosome -

Chromosomes are consists of 2 types of protein -

1) Histone protein ( almost 80% of total protein composition of chromosome . 5 types of histone proteins are found in chromosome - 1H1​​​​​​, 2H2a, 2H2b, 2H3,  2H4)

non histone proteins ( almost 20% of chromosomal protein composition .)

Nuclic acids -

Two types of nuclic acids are found in chromosome-

1) DNA or deoxyribonuclic acid [ DNA is composed of deoxy ribose sugar (pentose sugar), nitrogenous base ( adenine guanine, cytosine, thymine) phosphate group,] it is the major composition of eukaryotic chromosome.

2) RNA or ribonuclic acids [ ribose sugar (pentose sugar) nitrogenous base (adenine, guanine, cytosine, uracil) phosphate group

Beside this some ion (such as Ca+) could be the composition of chromosome