Key Area 6 Mutations And Key Area 7 Evolution Flashcards
What Is a mutation
It is a random and spontaous change in the genetic material
What causes mutation
Exposure to radiation
Exposure to chemical
What does a mutation result it
A protein not bring synthesised or a protien synthesis being altered
Types of mutations
Single genes mutation
Chromosomes
3 types of single gene mutations
Deletion
Insertion
Substitution
What is deletion with a single gene mutation
When a nucleotide is removed from a DNA strand
What is insertion in a single gene mutation
When a nucleotide Is added to the DNA strand
What is the result of the deletion on the single gene mutation
The strand is shorten
What I’d a result of a insertion in the single gene mutation
The strand is longer
Substitution in single gene mutation
When a nucleotide is swapped for another on the DNA strand
3 types of subsitions in single gene mutation
Missense
Nonsense
Splice-site
What is a missense mutation
Nucleotides being swapped for another leading a change of amino acids
What is a nonsense mutation
Results in a premature stop codon bring produced
What is a splice - site mutation
Sometimes are retained and/ or exons not included the mature mRNA transcription
What is the result of a missense mutation
Little effect or non functional protein
What is the result of a nonsense mutation
A shorter protien being synthesis
What is the result of splice- site mutation
May produce a non functional protien
What is a single gene mutation
It involves a chnage to one of the base pairs in the DNA sequence
What causes the frame shift mutation
Deletion and insertion
What is a chromosome structure mutation
They involve a change in the structure of one or more chromosomes
Types of chromosomes mutation
Deletion
Inversion
Translocation
Duplication
What is deletion for chromosomes mutation
This is when a section of chromosome is removed
What is inversion in chromosomes mutation
When a section of chromosomes is reversed
What is translocation in chromosomes
When a section of one chromosomes is added to another chromosomes that is not it’s homologus partner
What is duplication
Which a section of a chromosome is added from it’d homologus partner
Whata the result of chromosomes of deletion
Loss in genes
Result in Inversion for chromosomes
The formation of non - viable gametes
Whats the result of duplication
Set of genes being reapted. This can be potential beneficial is that duplication will bring an advantage
What is evolution
It is the gradual change in organisms over generations
What is evolution a result of
A genome variation
Why does evolution occur
To allow species to best adapt to their environment.
What is natural selection
It is the non random increase in the frequency of DNA sequence that increases survival and the non random decrease in the frequency of delirious.
3 types of natural selection
Stabilising
Directional
Disruptive
What happens in natural selection
Favorable characteristics are passed down the generations.
What can effect natural selection
Selection pressures
What are 4 selections pressures
Increases in competition
Changes to the environment
New diseases
New predators
What is the process of natural selection
Breeding population produce more off spring than the environment can support
Variations and adaptation can occur
Selection pressure kills of individuals
The strongest that are best suited to that particular niche survive
The organisms successfully breed passing on the favorable characteristics.
What happens during Stabilising
Both extremes are removed
Happens when the average phenotype is favorable and the extremes of the phenotype are suited against
What happened during directional selection
One of the extremes I’d favoured
3 types of selection
Stabilising
Directional
Disruptive
What happens during Disruptive selection
Both extremes are favoured
Two types of gene transfer
Horizontal gene transfer
Vertical gene transfer
What is horizontal gene transfer
This is when gene are passed between different individual of the same generation.
What cell type for horizontal gene transfer
Prokaryotes
Why does prokaryotes mutation happen faster
They transfer horizontal so that they can evolve faster
What is vertical gene transfer
It is when genes are passed from generation to generation through either sexual or asexual reproduction
Is vertical gene transfer a fast or slow process
Slow
Sexual vertical gene transfer
Since they have two parents it results in genetic variation
Asexual vertical gene transfer
They are genetically identical
What is speciation
A species is a group if organisms that have the ability to interbreed and produce fertile offspring.
If two differences species interbreed what will happen to their offspring
It will be infertile
What does the process if speciation involve
Isolation
Mutation
Natural selection
Stage 1 of speciation
An isolation is caused by a type of barrier
Geographical
Ecological
Behavioural
Stage 2 of speciation
Once a barrier has formed occur within the two different groups
Stage 3 of speciation
Organisms are exposed to selection pressures and those with the advantageous mutations eith survive
This results in a new group of organisms classed as a new species
Stage 4
Following natural selection the new group will feature those organisms with stringer genes
If the barrier is removed and the two siblings population meet. They will no longer be able to interbreed and produce fertile off spring thus I’d because thru are a new species
What are the two types of speciation in relation to barrier involved
Allopatric
Sympatic
Sympatic speciation
Ecological
Behavioural
Allopatric
Geographical
Stages of allopatric speciation
Population split
Population isolated
Gene mutation
Selective pressure
Variation
Speciation occurred
Barrier removed
What happens with sympatric speciation
Isolation that happens in the same ares without operation. The speed of new species produced is faster
Why is it important to have barriers
To prevent the flow of genes between different sub populations from happening. It is important to allow evolution to take place to allow for adaptation
What is species
They can interbreed to produce fertile off spring
What are the regions that closely related species occur together and can sometimes interbreed
Hybrid zone
