Polyploidy and its role in evolution
Polyploidy :- Deviation from the normal chromosome numbers in an organism is called polyploidy. It is of 2 types - 1. Aneuploidy 2. Euploidy 1. Aneuploidy :- • Definition :- Generally, the number of chromosomes in the genome of each somatic cell of an organism is fixed. If there is a decrease or increase in the number of 1 or 2 chromosomes in the genome, it is called as aneuploidy. It is found mostly in animals. It is rarely seen in plants. • Many types :- i. Nullysomy = (2n – 2) ii. Monosomy = (2n – 1) iii. Double monosomy = (2n – 1 – 1) iv. Trisomy = (2n + 1) v. Double trisomy = (2n + 1 + 1) vi. Tetrasomy = (2n + 2) 2. Euploidy:- • Definition:- Normally, each somatic cell of organism has 2 copies of the genome. When more than 2 copies of the genome are found in the somatic cells of organism, it is called euploidy. It is found only in plants. It is completely abs...