Chromosome Variation

Question 1

Polyploidy

Answer 1

Addition of complete sets of chromosomes

(I.e. > 2 sets of chromosomes)

Question 2

Aneuploidy

Answer 2

One or more individual chromosomes are added/deleted

Diploid genome which lacks a chromosome or has an extra chromosome

Question 3

Chromosomal rearrangement

Answer 3

Piece of chromosome is inverted, duplicated, deleted

Question 4

Monoploidy

Answer 4

Only one set of chromosomes

Question 5

Polyploidy

Answer 5

More than the normal number of sets of chromosomes (>2)

Question 6

Autopolyploids

Answer 6

The chromosome sets are all identical

Question 7

Trivalent

Answer 7

Three pairs of homologous chromosomes

Question 8

Bivalent

Answer 8

Two pairs of homologous chromosomes

Question 9

Univalent

Answer 9

A pair of homologous chromosomes

Question 10

Allopolyploids

Answer 10

An individual having two or more complete sets of chromosomes derived from different species

Question 11

Tetravalent

Answer 11

4 pairs of homologous chromosomes

Question 12

Somatic vs Gametes cells

Answer 12

Gametes always have HALF the chromosomes as the somatic cells

Somatic 2n = 46
Gamete n = 23

Somatic 2n = 14
Gamete n = 7

Somatic 4n = 28
Gamete 2n = 14

Somatic 6n = 42
Gamete 3n = 21

Question 13

Aneuploidy Types

Answer 13

Nullisomy: 2n - 2

Monosomy: 2n - 1

Trisomy: 2n + 1
Double trisomy: 2n + 1 + 1

Tetrasomy: 2n + 2

Question 14

Nondisjunction

Answer 14

Occurs when homologous chromosomes or sister chromatids do not separate in cell division

Question 15

Nondisjunction in meiosis II

Answer 15

Daughter cells will have (N+1), (N-1), (N) and (N) chromosomes