__________is  purine nitrogen base.

A DNA molecule is a large macromolecule consisting  of millions of nucleotides. Hence called as ___________.

When the centromere is slightly displaced from the centre  it is said to be __________.

Double helical structure of DNA was  given by ____________.

__________is a picture of  a person's chromosome.

Centromere present at the proximal end  is called ___________.

The _____________ bases are purine and  pyrimidines.

____________are the units  of heredity  and are  responsible for the characteristics features.

Diploid cells have _________homologous pairs.

When the  centromere is  centrally located it is called ______________.