Unit 3 Part 1 Flashcards
Mutations and gene editing
Mutations?
Any change to RNA or DNA base sequence of cell
What’s involved in DNA replication?
Enzymes
Transcription
Synthesis of RNA using DNA as template
What transcribes DNA to RNA?
Enzyme RNA polymers
Translation
Synthesis of polypeptides by ribosomes
What do ribosomes need to synthesize polypeptides?
mRNA and tRNA
What do mRNA and RNA do in translation?
mRNA
- Brings genetic code to ribosomes
RNA
- Brings amino acids to the ribosomes
Gene mutations
Change in nucleotide sequence of a gene
Types of gene mutations
Point mutations
- Changes one base in DNA sequence
Substitutional mutations
- When one or more nucleotide(s) in DNA sequences are replaced by another nucleotide
Insertion mutations
- When one or more nucleotide(s) are added to the DNA sequence
Deletion mutation
- Happens when one or more nucleotides are removed from DNA sequences
Single nucleotide polymorphism
Happens when a single nucleotide in a gene changes resulting in different amino acids in a protein
Allele
Gene in the population
- A mutation that creates a single nucleotide polymorphism produces and alternative version of an allele
Polymorphism
Occurrence of 2 different phenotypes w/in a population
What are the results of single nucleotide based solutions?
single nucleotide polymorphisms
Base substitution mutations
Single base substitution mutation changes the nucleotide sequence for 1 codon w/in a gene
Why could base substitution mutation not be able to change amino acid sequences?
Due to degeneracy of genetic code
- Genetic code is degenerate b/c 1 acid can be coded by more then 1 codon
How is a different protein sequence produced?
When a codon mutates to code for a different amino acid or a stop codon
Insertion mutation
Adds 1 or more nucleotides(s) to a gene
- Changes many codons as they are triplets of nucleotides
- All codons are changed after insertion
- Insertion mutation will release protein w/multiple different amino acids
Deletion mutation
Removes 1 or more nucleotide(s) from gene
- Changes many codons as they are triplets of nucleotides
- All codons are changed after deletion
- Deletion mutation will release protein w/multiple different amino acids
Frame shift mutation
Results from insertion/ deletion of nucleotides that are not in multiples of 3
- Changes all codons after mutation
Point Mutation
Changes 1 nucleotide in single codon
- Could change a singular amino acid in a protein
Frame shift mutation features
- Insertion/ deletions disrupt reading of codons in gene
- Polypeptides created by FSM are unlikely to function as many codons have different sequences of amino acids
Causes of gene mutation?
Naturally through DNA replication or in repair of damaged DNA
Mutagens
Agents that cause permanent, heritable changes to DNA of cells
High energy radiation of mutagens?
- High energy electromagnetic radiation like ultraviolet light
- x-rays, gamma lights = mutagens
Radioactive isotopes of elements release alpha and beta particles (mutagens)
