BIO120 UOFT TEST 1

SNP

Single nucleotide polymorphism

What does SNP let us see?

It lets us see the differences between individuals

Dioecy

The phenomenon of a species having distinct male and female organisms or colonies

What percentage of plants have dioecy?

7%

Bakers law

Long distance dispersal that favours selfing forms because a single individual can start a colony without mates or pollinators

Tangled bank hypothesis

There is an importance in spatial hetergoeneity found in a complex environment in the maintenance of sexual reproduction

Types of natural selection on quantative traits

Stabilizing selection (favours average traits)
Directional selection (favours on extreme)
Disruptive selection (favours both extremes)

Evolution of cyanide resistance

Alleles resisting cyanide are found at low percentage in population
Cyanide presence imposes selection
Resistance spreads
Individuals with resistance have a higher reproductive success
Eventually these genes increase over time

Lenski

Father of experimental evolution

E coli study

20 year experiment where 40, 000 generations were reproduced
Lenski observed how they adapted to only being fed vitamin C at big amounts every other day
They adapted by growing bigger nucleus to be able to break down lots of vitamin C at once and also store it

Gene

The functional unit of inheritance
Located on the chromosomes consisting of DNA
A DNA sequence composed of codons essential for a specific biological function

Princeton scholars

Peter and Rosemary Grant

Galapagos study

Conducted 35 year long study by Peter and Rosemary Grant
Witnessed adaptive radiation in 14 Galapagos finches

Stohastic

Unpredictable or random

Stohastic examples in evolution

Mutation
Recombination
Gene flow
Genetic drift

Genetif drift

Stohastic change in allele frequency due to random variation in fecundity and mortality

Scientific creationsim

Not supported by any empirical observation
It does not infer its principles from observation as does all science
Its assumptions leads to no testable or falsifiable hypotheses

Enzyme electrophoresis

Richard Lewontin

Discovered enzyme electrophoresis

Balance school of population structure belief

There is not a best or ideal genotype; balancing selection favours diversity

Founders of the Balance school of population structure

Ford and Dobzhansky

Inclusions of the balance school

Natural population
Low homozygosity
High polymorphism

Fishers fundamental Theorem of Natural selection

The rate of increase in fitness of a population at anytime is equal to its genetic variance in fitness

Founder of population genetics

Fisher

Classical school of population structure belief

The "wild type" is the best genotype, purifying selection reduces diversity

Inclusions of the classical school of population structure

Lab mutants
High homozygosity
Low polymorphism

Founders of the school of classical population structure

Morgan and Muller

Point mutation

Single base change

Insertion or deletion mutation

Jumping genes

Parthenogensis

Type of asexual reproduction where the off spring develop from unfertilized eggs

Hermaphrodittism

Enabling a form of sexual reproduction in which both partners can act as either female or male

Inbreeding depression

The reduction in fitness of inbred offspring in comparison with outcrossed offspring

Gene flow

The movement of genes from one population to another

Red queen hypothesis

Organisms must constantly evolve, adapt and proliferate not merely to gain reproductive advantage but also to simply survive while pitted against other ever-evolving organisms in an every-changing environment

Selection processes of genetic diversity

Purifying negative selection
Positive selection
Balancing selection

Mutation

A stable change in DNA sequence resulting in a change of genotype
Occurs at a very low but variable rate in all organisms
To be useful must occur in germs cells because somatic mutations are not inherited thus no use to evolution

Artificial selection on quantative traits

Involves controlled breeding and selection for many generations
Selection responses demonstrates that abundant genetic variation exists for polygenic traits
No key info on population genetics because comparative studies are difficult as traits studied are often within a group

Genome

The entire organism's DNA including both genes and non-coding regions

Maintenance of genetic variation/diversity?

Mutation-selection balance
Selection maintaining variation

Characteristics of mutation

It is unstoppable, can't be controlled, it's rate depends on the gene it is mutating and the environment can insult

Theropods

Common ancestor of birds and reptiles

Neil Shubbin

Predicted the right layer of rocks for strata that would show where the transitional spot of fish to reptiles would be

Trees down

An evolutionary expression stating that reptiles had feathers that helped them glide down for food or escaping preadators before actually flying and becoming actual birds

Ground up

An evolutionary expression stating that reptiles had feathers to let them open-arm run and leap to catch prey

Atavisms

throwback genes present but normally turned of

Synonyme for dead genes

Pseudogenes

Recapitulation

A repetition of an evolutionary process from the past in the present during the stages of development/ growth

Barry Hall

Did study on E coli where they were feed lactose. Eventually they developped an enzyme that could break down lactose and digest it

Scott Caroll

Predicted that bugs changing host fruits with different sizes would change their beaker size. Prediction was correct

Arthur Weis

Predicted that flowers that lived in drought environments would eventually adapt to flowering early before the drought season.