biology 2 pt2

Evolution, macroevolution, diseases ,pop ,micro evolution, species, prokaryotic, eukaryotic

Evolution

Descent with modification

Co-evolution

Two organisms that have evolved together

Descent

generation to generation

Modification

Change 

Descent with modification

Genetic change in a population or species over  generations 

Evolution (1.)

Genetic change in population

Natural Selection

Those w/ better traits—> leads to MORE EVOLUTION GROWTH, accumulation of traits

What does natural selection lead to?

Continuous natural selection will EQUAL TO evolution

How is evolution seen as?

Seen as adaptation w/ accumulation of traits in a growing pop

Artificial breeding (or selective breeding)

Breeding of domesticated crops/animals, by choosing mates w/ desirable traits

Anti-biotics

Drugs that kill/inhibit BACTERIA, but can become useless if bacteria resists

What resists anti-biotiics?

MRSA, MALARIA(cannot be gone) mosquitos can evolve faster than pesticides,

Fossil record

Ordered sequence of fossils found in layers of rock, w/ older fossils/new

Where are older fossils buried?

At the very bottom

Where are new fossils buried?

Near the surface

Radiometric dating

Finding out age of fossils BREAKING DOWN RADIOACTIVE ISOTOPES, evidence for evolution

MACROevolution

MAJOR CHANGES e.g new species, mass extinction

Speciation

ancestral species evolving into 2 different species

What are the two ways branches split (speciation)?

Non branching and branching

Non-branching (speciation)

Ancient pop CHANGING OVER TIME EVOLVING to a DISTINCT NEW SPECIES

Branching

Population splits into TWO or more populations evolving into new species different from each other

What do fossil records demonstrate?

That structures evolve to at first serve one purpose and then change to serve another

e.g humans being upright led to having two legs

Flowers evolving from non-flowers

What does lineage of species show?

Shows evolution of new structures (fossils), so how they’ve adapted to there environment

Mass extinction is an example of…

Macroevolution

Systematics

Classifications of organisms to show evolutionary relationships (reflects evolutionary history)

Phylogenetic trees

A hypothesis diagram about evolutionary history of related species (demonstrate, fossil records/DNA)

Cladistics

The history of ancestral species that are then placed on a phylogenetic tree, study of clades

Clades

The group of ancestral species themselves

Out group

Species diverged before common ancestor (e.g frog)

In group

Characteristics that separate it from a outgroup (e.g snakes, lizards, birds)

What is an example of a outgroup and ingroup?

Baboon- out group and ingroup Orangutan, Gorilla, Chimp, Human in

Infectious diseases

Diseases caused by pathogen that invades tissue

Genetic disease

Not caused by a pathogen but a defect in genes

Pathogen (in this case its a bacteria/parasite pathogen not a virus)

Bacteria and virus or other micro organism e.g gastro enteritis

Vector-born diseases

Diseases transmitted from person to person through an insect (e.g mosquitoes)

What do pathogens do?

Needs the host to develop

Bacterial Infection can be cured with…

Anti biotics

Useful Bacteria examples are…

Sewage treatment and bioremediation

Sewage treatment

sewages has to be treated w/ bacteria that treats it & turns it less harmful

Bioremediation

An environmental clean up using living organisms(bacteria, fungi, plants) to degrade hazardous pollution

What is an important fertilizer?

Nitrogen

What can speciation lead to?

Can lead to a population no longer being able to meet/mate because a species evolve into 2 different species w/ their own path

Graduated model

A model for a evokution of new species (NOT always LINEAR)

Punctuated equilibirum

Periods of NO CHANGE, INTERRUPTED by a BURST of SPECIATION

Example of punctuated equilibrium

Mammals NOT CHANGING UNTIL SPECIATION following extinction of dinosaurs

Allopatric speciation

Populations separated physically geographically into 2

Sympatric speciation

The emergence of a new species, in the midst of parent population WITHOUT ISOLATION

Example of sympatric speciation

In plants accidents during cell division can result in organisms w/ multi sets of chromosomes, producing new stuff

What did sympatric speciation eventually took part in?

Took part in the creation of food crops (apples, coffee, wheat) errors caused self fertilization producing modern bread

What does unequal reproduction lead to?

Unequal reproductive success leads to natural selection

What has evolution done?

Evolution has shaped life on earth through natural selection

Do individuals evolve?

That is FALSE

Changes of population refers to…

Evoution

Population

group of individiuals living at the same time/place

Population is the..

The smallest unit that can evolve

gene pools

The forms of all genes in a population at any one time

How does genetic variations occur?

Mutations

Mutations

random changes to DNA

How is natural selection involved w/ gene pools?

Natural selection the more it occurs the more gene pools mix and that gets passed down INCREASING frequency

MICROevolution

Small scale of evolution, changes to generations

Genetic Variation

Changes to genetic makeup of a population

What can mutations cause or do?

create different version of genes, in multi varieties, can BREAK down into 2 and can harm or change survival rates

What are 2 things to know about genetic variations?

Sexual recombination and mutations

Sexual recombination

Produces new arrangements of existing genes during formates of gametes, chromosomes exchanges pieces w/ one another

Independent assortment

Basically how eye color genes occur, the process of sorting genes to get passed down, that don’t affect someone, (genes for different traits are sorted separately from one another during the formation of reproductive cells (gametes)

Darwinian fitness

Contribution that a individual makes to gene pool of next generation compared to others (producing offspring with good traits contributing to population)

What are mechanisms of evolution?

Genetic drift, bottleneck, founder effect, gene flow, sexual selection

Genetic Drift ( important)

a CHANGE in GENE POOL due to CHANCE

Example of genetic DRIFT

In LARGE POP death due to migration has SMALL IMPACT

In SMALL POP random changes AFFECT gene pool

Bottleneck

Change in gene pool due to REDUCTION in POP size

Founder effect

Change in gene pool due to a SMALL POP (so not reduction of pop size)

Example of bottleneck occuring

Due to cheetahs having a reduction in pop size it led to the low variation in gene pool, which is why they look the same today

Gene FLOW (important)

the TRANSFER OF GENES from ONE POPULATION to ANOTHER (due to migration)

What is an example of gene flow?

Humans

Sexual selection

Individuals are more likely to attract mates that have more offspring (e.g males having characteristics that attract females, leading to these genes to contribute to gene pool)

Species

A population that can produce healthy offspring

Can similar appearance mean two animals are the same species?

E.g No birds can be both be birds but are not the same species because THEY CANNOT BREED

Who does the USUAL definition of species not apply to?

Fossils and those who reproduce Asexually

Reproductive Barriers

Separation of species due to diff interbreeding process/biologically

Examples of reproductive barriers

Behavioral isolation, habitat isolation, hybrid weakness, mating time difference, mechanical incompatibility, gametic incompatibility

Behavioral Isolation

Species developing different methods to get mates so leads to different ways to mate w/ each other (separating species)

e.g birds singing to attract mates but frogs won’t react to that

Mating time differences

Species reproducing at different times

Habitat Isolation

Living in different habitats so species never meet, separated

Mechanical Incompatibility

Anatomy incompatible different species, so bees and dogs can’t mate

Gametic Incompatibility

Diff egg/sperm that can’t fertilize,

Hybrid Weakness

The offspring of 2 diff species that could be infertile/sterile

From where did eukaryotic cells evolve?

Eukaryotic cells evolved from prokaryotic cells

Old eukaryotic cells are ancestors of..

Bacteria, fungi, plants, animals

What is one prominent feature of eukaryotic cells?

They all include Endomembrane

What does the Endomembrane system include?

Endoplasmic reticulum, nuclear envelope, golgi apparatus, vesicles, plasma membrane

Endosymbiosis

When 1 species lives inside another host species

What are the 2 eukaryotic organelles that evolved from small free living prokaryotes?

Mitochondria and chloroplasts

What has endosymbiosis led to?

HAS benefitted all organisms, offering evolutionary advantadge, leading to interdependence