The fundamental importance of chromosomes is that they contain DNA, or deoxyribonucleic acid, the substance that contains every organism's genetic code. When a cell divides, its chromosomes must first replicate. Cells divide in two basic ways – mitosis and meiosis. The latter type of division incorporates the former.
All cetaceans exhibit similar surface behaviour like breaching,spy hopping,spouting etc..they are huge mammals who live in marine water.they live as a family
