1.4 Flashcards
What are mutations?
Changes in the DNA that can result in no protein or an altered protein being synthesized
Mutations can occur due to various factors and can significantly impact biological functions.
What are the three types of single gene mutations?
- Substitution
- Insertion
- Deletion
Jingle gene mutations involve alterations in the DNA nucleotide sequence.
What is a substitution mutation?
The replacement of one base in the DNA sequence
This type of mutation can lead to changes in the amino acid sequence of proteins.
What is an insertion mutation?
The addition of one base to the DNA sequence
Insertions can lead to frame-shift mutations, altering the reading frame of the genetic code.
What is a deletion mutation?
The removal of one base from the DNA sequence
Deletions can also cause frame-shift mutations, impacting protein synthesis.
What are the three effects of substitution mutations?
- Missense: one amino acid is changed for another
- Nonsense: premature stop codon
- Splice-site: introns may be retained or exons removed
These effects can significantly alter protein function.
What is a frame-shift mutation?
A mutation that results from insertions or deletions, changing all subsequent codons and amino acids
This can have a major effect on protein structure and function.
What are chromosome structure mutations?
Mutations that alter the number of chromosomes or their structure
Substantial changes can often be lethal.
What is translocation in chromosome mutations?
A section of a chromosome is added to a chromosome that is not its homologous partner
This can lead to various genetic disorders.
What is inversion in chromosome mutations?
A section of a chromosome is reversed
This mutation can affect gene function, such as causing Haemophilia A.
What is duplication in chromosome mutations?
A section of a chromosome is added from its homologous partner
This can cause genetic disorders like Pallister-Killian syndrome.
What is deletion in chromosome mutations?
A section of a chromosome is removed
This can lead to conditions such as Cri-du-chat syndrome (chromosome 5).
