5-Mitosis, meiosis and chromosome abnormalities

Question 1

What are the main features of a chromosome?

Answer 1

Sister chromatids
Centromere
Euchromatin
Heterochromatin

Question 2

How many pairs of chromosomes do we have and what are they made up of?

Answer 2

23 pairs
Made up of 44 autosomes and 2 sex chromosomes
46 chromosomes in total

Question 3

What is a chromosomal abnormality?

Answer 3

Change in Chromosome number structure or something that happens during meiosis

Question 4

What is the role of telomeres?

Answer 4

Help prevent damage

Question 5

What are nucleosomes?

Answer 5

DNA wrapped around eight histone proteins

Question 6

What is chromatin?

Answer 6

Network of DNA and proteins that make up chromsomes during interphase

Question 7

What is heterochromatin?

Answer 7

Highly condensed and genetically inactive- mainly at centromeres

Question 8

What is euchromatin?

Answer 8

Lighter staining relatively open structure where genes may be accessed and are active. Includes protein coding genes

Question 9

What is a telomere?

Answer 9

Cap at the end of chromosome

Question 10

What is a centromere?

Answer 10

1/ chr. Position on chr where 2 sister chromatids are joined

Question 11

What is the p arm of a chromosome?

Answer 11

Short arm of the chromosome

Question 12

What is the q arm of a chromosome?

Answer 12

Long arm of the chromosome

Question 13

What is an autosome?

Answer 13

Any chromosome that is not a sex chromsome

Question 14

How are chromosomes classified?

Answer 14

Based on the position of the centromere
Size
Banding pattern

Question 15

What is mitosis?

Answer 15

The process of somatic cell division

Question 16

What is meiosis?

Answer 16

Generates haploid gametes-4 daughter cells

Question 17

What happens at fertilisation?

Answer 17

Combines two haploid gametes to give a diploid zygote

Question 18

How is diversity brought about during meiosis?

Answer 18

Crossing over- recombination

Question 19

What is mitosis used for?

Answer 19

Growth and repair

Question 20

What is meiosis used for?

Answer 20

Sexual reproduction

Question 21

Where does mitosis occur?

Answer 21

Somatic cells

Question 22

Where does meiosis occur?

Answer 22

Germline cells

Question 23

What is meant by the term ploidy?

Answer 23

Wrong number of complete chromosome sets

Question 24

What is meant by the term aneuploidy?

Answer 24

Specific additional or missing chromsomes

Question 25

What is meant by reciprocal translocations?

Answer 25

2 Chromosomes swap non-homologous regions

Question 26

What is meant by matrilineal?

Answer 26

inherited primarily from the mother

Question 27

What is meant by heteroplasmy?

Answer 27

Mix of mutant vs wild type