Lectures 6-9 - Chromosome Variation

Question 1

What is polyploidy?

Answer 1

More than the normal set of chromosomes, Tripoid, tetraploid

Question 2

How does autopolyploidy occur in mitosis vs meiosis?

Answer 2

Mitosis: no cell division
Meiosis: non-disjunction in meiosis 1

Question 3

Problems with polyploidy

Answer 3

Most are sterile

Question 4

What is an allopolyploid?

Answer 4

Result of cross between 2 or more species

Question 5

What occurs in animals for polyploidy?

Answer 5

Inter species crosses result in a sterile animal

Question 6

What is aneuploidy?

Answer 6

Diploid genome that lacks a chromosome or has an extra chromosome

Question 7

Non disjunction in meiosis 1?

Answer 7

Leads to trisomic and monosomic cells

Question 8

Non disjunction in meiosis 2?

Answer 8

Results in trisomic, monosomic, and two normal diploids

Question 9

When do frequency of trisomies increase?

Answer 9

Age

Question 10

What is a deletion?

Answer 10

Missing chromosome segment

Question 11

What is a duplication?

Answer 11

Extra chromosome segment?

Question 12

What is hypoploidy?

Answer 12

Less genetic material such as deletion of chromosome segment or loss of entire chromosome

Question 13

What is hyperploidy?

Answer 13

More genetic material such as duplication of chromosome segment or gain of a chromosome

Question 14

What is a translocation?

Answer 14

Occur when segment from one chromosome is detached or reattached to different chromosome

Question 15

What is a reciprocal translocation?

Answer 15

Pieces of two no homologous chromosomes are exchanged without any net loss of genetic material

Question 16

What is a compound chromosome?

Answer 16

Fusion of homologous chromosomes

Question 17

What is a robertsonian translocation?

Answer 17

Formed by fusion of two non homologous chromosomes at their centromeres