Mutations

Question 1

Gene Mutation

Answer 1

A single gene is altered, destroying or changing the traits normally produced by that gene

Question 2

Chromosomal Mutations

Answer 2

All or parts of a chromosome are affected/altered

Question 3

Somatic (body cells) mutations

Answer 3

These are when body cells are affected.
- Only the individual with the mutation is affected.
- Mutation passed on during mitosis to the daughter cells.

Question 4

Germinal/Germline mutations

Answer 4

Occur when the repro cells are affected by the mutation.
- Mutation may be passed on through gametes
- Individual may not be affected

Question 5

What are mutagens?

Answer 5

Substances that cause mutations

Question 6

What are the known mutagens?

Answer 6

Mustard gas
Formaldehyde
Sulphur Dioxide
Some Antibiotics
Radiation
After effects of atomic and nuclear explosions

Question 7

Albinism

Answer 7

Due to one missing protein there is an absence of pigments on the skin, hair and eyes

Question 8

Duchenne form of muscular dystrophy

Answer 8

Caused by either: mutation in mother or male zygote
Results in wasting of muscle tissue - replaced by fatty tissue as boys get older

Question 9

Cystic Fibrosis

Answer 9

Mutation on chromosome 7, controls manufacture of 1480 amino acids that make up a protein that regulates the passage of chloride ions across the cell membrane
Can cause: persistent coughing, salty-tasting skin, wheezing, and digestive problems.

Question 10

Deletion

Answer 10

Loss of a piece of DNA from a chromosome.
Deletion of a gene or part of a gene can lead to a disease or abnormality.

Question 11

Duplication

Answer 11

Production of one or more copies of any piece of DNA, including a gene or even an entire chromosome.

Question 12

Insertion

Answer 12

A type of chromosomal abnormality in which a DNA sequence is inserted into a gene, disrupting the normal structure and function of that gene.

Question 13

Translocation

Answer 13

Breakage and removal of a large segment of DNA from one chromosome, followed by the segment’s attachment to a different chromosome.

Question 14

Inversions

Answer 14

The order of the genes is changed on the chromosome, as a result of a chromosome break.

Question 15

Non-Disjunctions

Answer 15

A change in the chromosome number of meiotic daughter cells.

Question 16

Trisomy

Answer 16

Condition where an individual inherits an extra copy of a chromosome.

Question 17

Trisomy 21

Answer 17

Down Syndrome -
Extra copy of chromosome 21 results in characteristic facial appearance variable degrees of intellectual disability and physical abnormalities.

Question 18

Trisomy 13

Answer 18

Patau Syndrome
Extra chromosome 13. Produces individuals with intellectual disability, a small head, extra fingers or toes, a cleft palate and/or cleft lip and malformations of the ears and eyes.

Question 19

Trisomy 18

Answer 19

Edwards Syndrome
Results in an intellectual disability & defects in the eyes, ears, hands and head.

Question 20

Monosomy

Answer 20

Individual is missing a chromosome.
Results in severe malformations and often miscarriage.

Question 21

Partial Trisomy

Answer 21

Part of an extra chromosome is attached to one of the other chromosomes.

Question 22

Trisomy on sex chromosomes

Answer 22

XXY or XYY

Question 23

Effects of Mutations

Answer 23

The variations caused by mutations may have advantageous or disadvantageous effects.

Question 24

Advantageous Mutations

Answer 24

Sickle Cells trait
Resistance to Atherosclerosis
Immunity to HIV/AIDS