This document defines and describes various types of numerical changes in chromosomes, including euploidy, aneuploidy, polyploidy, and autopolyploidy vs allopolyploidy. It provides examples of polyploidy levels from haploidy to hexaploidy. It also discusses aneuploidy conditions including monosomy, nullisomy, trisomy, tetrasomy, pentasomy, hexasomy, and heptasomy. The key differences between autopolyploidy and allopolyploidy are that autopolyploidy involves multiple copies of chromosomes from the same species, while allopolyploidy involves chromosomes from different species.

1. NUMERICAL CHANGES IN
CHROMOSOME
ABDUL JALEEL K
ASSIST.PROFESSOR
GOVT. COLLEGE KASARAGOD
jaleelkabdul@gmail.com

2. EUPLOIDY
ANEUPLOIDY

3. EUPLOIDY
HAPLOIDY
(N)
POLYPLOIDY
3N,4N,5N
DIPLOIDY
2N

4. POLYPLOIDY
TRIPLOIDY(3
N)
TETRAPLOID
Y(4N)
PENTAPLOID
Y(5N)
HEXAPLOIDY
(6N)

5. ANEUPLOIDY
MONOSOMY
2N-1
NULLISOMY
2N-2
TRISOMY
2N+1
TETRASOMY
2N+2
PENTASOMY
2N+3
HEXASOMY
2N+4
HEPTASOMY
2N+5

6. HYPERPLOIDY
•TRISOMY
•TETRASOMY
•PEMTASOMY
•HEXASOMY
•HEPTASOMY
HYPOPLOIDY
•MONOSOMY
•NULLISOMY

7. • an organism whose cells
have more than 2 sets of
chromosomes derived
from the same species.
Autopolyploidy
• Allopolyploid is an
organism whose cells
have multiple sets of
chromosomes derived
from a different species.
Allopolyploid

8. Autopolyploidy Allopolyploidy
The chromosome
complement consists of
more than two copies of
homologous chromosomes
The chromosome
complement consists of
more than two copies of
chromosomes derived
from different species
It arises by the fusion of
gametes of the same
species
Arises by the fusion of
gametes of the
different species
Does not undergo meiosis since it has
arisen from one parent
Can undergo meiosis
The cell contains homologous
chromosome sets
All chromosome sets of an allopolyploid
cell are not homologous
Mainly caused by non-disjunction of
chromosomes
Caused by mating of different species
Eg. wheat, oats, sugar-cane,
potato, peanut, banana,
and coffee
wheat and animals such
as mules

9. Diagram from
https://www.pathwayz.org