Mutations Flashcards
What is a mutation? and what does it lead to?
A mutation is a permanent change in the DNA sequence of a gene. Mutations in a gene’s DNA can alter the amino acid sequence of the protein encoded by the gene.
What are the two main types of mutations?
(1) Chromosomal Mutations
(2) Gene mutations
A huge molecule made up of nitrogenous bases.
DNA
A process that produces the sex cells with half the chromosomes of a body cell.
Meiosis
Strands of genetic material.
Chromosome
Factors that control traits.
Gene
What leads to errors in the DNA?
(1) DNA replication
(2) Physical and chemical mutagens:
- UV rays
- ionizing radiation
- Heat
Mention types of DNA repair.
1) Direct repair
2) Excision repair
3) Mismatch repair
4) Recombination repair
Mention types of gene mutations.
1) Point mutation
2) Frameshift mutation
Mention types of chromosomal mutations.
1) Deletion
2) Inversion
3) Non-disjunction
4) Duplication
5) Translocation
What are the two ways in which mutations can occur?
1) Inherited
2) Acquired
Mention the types of gene mutations.
1) Synonymous (silent mutation)
2) Non-synonymous (missense)
3) Nonsense
4) Readthrough
What’s a chromosome?
Chromosomes are coiled up DNA strands with proteins called histones. Humans have 23 pairs of chromosomes. In normal conditions, chromosomes are inherited in tact.
What is a karyotype?
A karyotype is a picture of chromosomes lined up to look at and compare.
What is a point mutation? And what can it cause?
A point mutation is a mutation which occurs at one point (one nucleotide/base) is substituted for another.
It can cause sickle cell anemia.
What is frameshift mutation?
These include insertion of an extra nucleotide or deleting a nucleotide which shifts the reading frame of the genetic message.
Mention diseases that may be cause due to mutations.
1) Cancer - overexposure to UV light
2) Cystic fibrosis
3) Sickle-cell disease
4) Hemophilia
5) Down syndrome
