Inheritance & Environment Flashcards
What can cause chromosomal alteration?
Environmental factors such as radiation or other chemical triggers or randomly
What is deletion? ( chromosomal alteration)
When one gene is completely deleted/ eliminated
What is duplication? (Chromosomal alteration)
A gene is duplicated in the chromosome
What is inversion? (Chromosomal alteration)
Genes a inverted into opposite sequence
What is reciprocal translocation? (Chromosomal alteration)
Gene inter changed between homologous & non-homologous chromosome
What on the 4 kinds of chromosomal alteration?
Deletion, duplication, inversion & reciprocal transaction
When do mutations typically occur?
During gene expression, transcription, replication or translation
What is a Missense mutation?
When one amino acid is replaced with a different amino acid due to a Singh nucleotide substitution which alters genetic code
What is a nonsense mutation?
Single nucleotide replacement creating a stop codon too early
What is a frame shift mutation?
Deletion/insertion of a nucleotide causing the reading frame to shift, the most severe
What is a silent mutation?
Whe one nucleotide is replaced but it does not change the amino acid which is coded for
Are mutations selective or random?
Random
When do mutations occur?
All the time
Why does high mutation rate increase survival rate of a species?
Creates less homozygous & thus increases the chances of off spitting laving the new necessary variation of genes. Increases gene variation, diversesifices
Who was the first philosophers that started talking about evolutionary theories? A what was his theory ? (Now out dated )
Plato, typological thinking: every organism was an example of a perfect essence created by God & organisms where changing, focused on studying the perfect essence
What is typological thinking?
Platos theory that species are unchanging & variations are unimportant/ misleading
What evolutionary theory did Aristotle develope?
The scale of nature
What does the scale of nature theories about evolution?
Species are fixed types of organisms that were organized into sequence based on increased size a complexity (on a latter).
When was Aristotles theory & thinking dominant until?
1700 ‘s
What was Lamarck’s evolutionary theory?
Organisms were changing through time because of inheritance of acquired characteristics
Who introduced the idea of inheritance of acquired characteristics?
Lamarck
What did Lamarck believe happened to life experience?
He believed it was passed on to off spring
What is Darwins evolutionary theory called? & how many postulates?
Natural selection,4
What do the 4 postulates state?
- Individual organisms vary in traits they possess
- Some trait differences are heritable
- Survival and reproductive success are highly variable
- individuals with certain heritable traits are more likely to survive / reproduce
When does natural selection occur?
When individuals with certain heritable traits produce more surviving offspring than individuals without those traits therefor a frequency of the selected trait increases from one generation to the next
What is the outcome in natural selection?
A change in allele frequencies in a population over time
Does evolution happen to individuals?
No, population
Definition of natural selection
Increases frequency of certain alleles, alleles that increase fitness in specific environment
What is an example of artificial selection?
Genetically modified food products
Definition of genetic drift
Allele frequencies change randomly
Definition of gene flow
New individuals introduce new alleles to the population (ex wolfs from Europe bling mixed with wages from America).
What 2 things cause genetic drift?
- Founder effect
- Genetic bottle neck
What is the founder effect? (genetic drift)
A change in allele frequency that occurs when a new population is established