1
Q
Mutation Type 1: Point Mutations
A
- May be caused by errors in DNA replication
- Includes; base pair substitution, deletion and insertion
2
Q
Base Pair Substitution
A
- Where one or more base pairs is replaced by another base pair
- Overall effect depends on gene in question
- Example: A-T is replaced by G-C
3
Q
Base Pair Deletion
A
- Where 1 or more base pairs is omitted
- Changes the reading of the code from that point on
- Frameshift mutation
- Big effects usually
4
Q
Base Pair Insertion
A
- Where 1 or more base pairs is added
- Changes the reading of the code from that point on
- Frameshift mutation
- Big effects usually
5
Q
Mutation Type 3: Changes in Chromosome Number
(Atypical numbers)
A
- Can be caused by non-disjunction
an individual has more or fewer chromosomes- Members of a homologous pair may not separate properly during meiosis I
- Sister chromatids fail to separate during meiosis II
- In mitosis of early embryo, error is passed on to many body cells
- Includes: Aneuploidy and Polyploidy
6
Q
Aneuploidy
A
- One more or less chromosome
- Offspring has an abnormal chromosome number
- Includes: Trisomy and Monosomy
7
Q
Trisomy
A
- Where the cell has 1 extra chromosome
- ie. Down’s syndrome in humans
8
Q
Monosomy
A
- Where the cell has 1 less chromosome
- One less from a homologous pair
9
Q
Polyploidy
A
- One of more entire SETS of chromosomes
- Where the organism has more than 2 complete sets of chromosomes
- Does not happen in humans
- Rare in animals but relatively common in plants
10
Q
What are mutations caused by?
A
Mutagens, or substances that damage DNA by changing the genetic code
11
Q
What are the 3 major types of mutagens to exist?
A
- Physical Mutagens
- Chemical Mutagens
- Biological Mutagens
12
Q
Physical Mutagens
A
- There’s physically strike the DNA and damage it
- Ex. Radiations (UV light)
13
Q
Chemical Mutagens
A
- These chemically damage/alter DNA
- Ex. Nicotine, Mercury
14
Q
Biological Mutagens
A
- Microscopic virus or bacteria that damage DNA
- Ex. HPV
15
Q
Carcinogens
A
- Mutagens that are known to cause cancer
- Way mutagens can be further classified
16
Q
Teratogen
A
- Mutagens that are known to cause birth defects (during fetal development)
- Way mutagens can be further classified
17
Q
Mutagen effects for multi-celled organisms that are already developed
A
Mutations tend to cause tumours in damaged tissue, which can then progress to cancerous tumours
18
Q
Mutagen effects for multi-celled organisms that are undeveloped
A
- Mutations may affect embryos/fetuses, which can eventually cause birth defects that will then show up in the offspring after birth
- They could also be good/positive mutations
Genetics Unit Test
flashcards
Decks in class (5)
# Cards
