Explain genes.

Gene is a physical and functional unit of heredity which is made up of DNA.

Every gene comprises of the particular set of instructions either for protein-coding or for a particular function.

Hence, genes are responsible for heredity.

Each individual has two copies of each gene out of this one is inherited from each parent.

Our parents have inherited one set of genes from our grandparents and our parents have passed one copy of genes to us.

Therefore we resemble our grandparents.