Chromosomes & Genomes

Question 0

What do DNA wrap around and form when making chromosomes?

Answer 0

His tone protein and it forms a nucleosome

Question 1

What are chromosomes?

Answer 1

Thread-like structures composed of DNA and protein, and visible in the cells during mitosis and meiosis

Question 2

A cell with one set of chromosomes are…

Answer 2

…haploid

Question 3

A cell with two sets of chromosomes are…

Answer 3

…diploid

Question 4

A cell with many sets of chromosomes are…

Answer 4

…polyploid

Question 5

What is the short arm of a chromosome called?

Answer 5

p (petite)

Question 6

What is the long part of the chromosome called?

Answer 6

q

Question 7

What are the short and long arm held together by?

Answer 7

Centromeres

Question 8

Do every chromosome have the same size and shape?

Answer 8

No, no two non- homologous chromosomes have the same size or shape

Question 9

Name three chromosomal changes that can occur.

Answer 9

Duplication
Deletion
Inversion

Question 10

What happens in a duplication chromosomal change?

Answer 10

Part of the chromosome is repeated

Question 11

What happens during a deletion chromosomal change?

Answer 11

Part of the chromosome is deleted

Question 12

When does the chromosomal changes of deletion and duplication occur?

Answer 12

Cross-over in mitosis (Prophase 1)

Question 13

What happens in a inversion chromosomal change?

Answer 13

Reverses part of the chromosome

Question 14

What is translocation?

Answer 14

When part of a chromosome is transferred to another

Question 15

What is non-reciprocal translocation?

Answer 15

Result in one chromosome with a deletion and the other with an addition

Question 16

What is reciprocal translocation?

Answer 16

When a part of a chromosome is added to another but the original chromosome isn’t changed

Question 17

What is it called when a whole chromosome arm is translocated?

Answer 17

Robertsonian Translocation

Question 18

Why do humans have one less chromosome than the rest of the great apes?

Answer 18

Due to a translocation of two chromosomes during the evolutionary history of humans AFTER they diverged from their last common ancestor with the chimps

Question 19

What is a karyotype?

Answer 19

Karyotypes are the conventional way of organising chromosomes to assist in analysis

Question 20

What are homologous chromosomes?

Answer 20

Homologous chromosome pairs are identified by size and the location of their centromere!

Question 21

How are homologous chromosomes identified?

Answer 21

Same size, shape and banding pattern

Question 22

What does the karyotype of humans consist of?

Answer 22

23 pairs of chromosomes.
22 pairs of homologous autosomes
1 pair of sex chromosomes

Question 23

What is trisomy?

Answer 23

When you have three chromosomes instead of the normal two

Question 24

What is monosomy?

Answer 24

When you have one chromosome instead of the normal two.

Question 25

How does trisomy occur?

Answer 25

Results in one gamete having two copies of a chromosome, and one gamete having no copies of the chromosome

Question 26

How many sex chromosomes are there?

Answer 26

2 X Chromosome Y Chromosome

Question 27

What determines a male?

Answer 27

The SRY gene on the Y chromosome

Question 28

What is a genome?

Answer 28

All of the genetic information (the base pairs) found in one complete set of an organisms chromosomes.

Question 29

Can there only be one genome?

Answer 29

No, mitochondria and chloroplast have set of chromosomes too. There can be mitochondrial genome and chloroplast genome

Question 30

The study of genomes is called?

Answer 30

Genomics

Question 31

Does the size of a genome determine the complexity of an organism?

Answer 31

No it does not

Question 32

What is so important about genomes?

Answer 32

The power of genomes comes from comparing the similarities and differences in the genomes of different species

Question 33

What is the study of comparing genomes?

Answer 33

Comparative genomics

Question 34

How can comparative genomics be useful?

Answer 34

Comparative genomics is a useful tool in studying evolutionary relationships between different organisms