Biodiversity Bio

A3.1, A4.1, A4.2, D4.1

Describe variation

• No 2 species are the same

• Variation exists between all organisms

• Without variation there is no life

Who created the Morphological Concept

Carl Linnaeus

What is the Morphological Concept?

• A classification of species based on look

How is binomial nomenclature formatted?

Genus the Species. 1st letter of genus is capitalized, species name italicized 

What is the biological species concept?

Defines a species as a population whose members can interbreed and produce fertile offspring. 

Pros of BSC

• simple, widely accepted definition

• focus on reproductive isolation

Cons of BSC

• cannot be applied to asexual organisms, extict species,

Species definition

A group of organisms that can breed and produce fertile offspring

Speciation definition

formation of a new species from the splitting of one pre-existing species into two or more new species.

Possible causes of speciation

• sympatric

• allopatric 

• sudden event 

Cause of speciation: Sympatric definition

Reproductive barrier preventing/limiting interbreeding between two pop. 

Cause of speciation: allopatric definition

physical barrier that might exist between two pop

Peripatric

Small population of a species colonizes somewhere new and become isolated

Parapatric

 Different environmental factors lead to a new species 

How many chromosomes do humans have?

46

How many chromosomes do chimps have?

48

Karyogram?

Image of a karyotype

Karyotype?

Appearance and # of chromosomes in cell from tallest to smallest, with gender chromosomes at bottom.

When are karyograms taken?

metaphase of mitosis

Why are chimps and humans related?

• Common ancestor

Genome?

all genetic material of an organism

What is single nucleotide polymorphism?

a variation in a single DNA building block, or nucleotide, found in at least 1% of the population

What can genome mapping be used for.

help us reclassify certain species into genuses and families they are more closely related to. AKA phylogenetics

E coli genome size

5 million

yeast genome size 

12 million

fruit fly genome size 

140 million genome size 

frog  genome size

??

People gene size

3 billion

What is evolution?

Change in heritable traits over time

What can evolution result in?

speciation

What is some evidence of evolution?

• study of fossils

• selective breeding 

• comparative anatomy 

• nucleotide and amino acid sequences 

What is the use and disuse theory?

structures used to strengthen, develop and enlarge, while ones that are not used weaken.

Charles Darwin’s idea of evolution?

• Comes from natural selection

• certain traits are heritable and if they increase ability to survive they will be passed down to next generation

Cons of Darwin’s evolution?

• likey to never be falsified 

molecular phylogeny

comparative analysis of the sequences of the bases in DNA and RNA, and the amino acids in proteins to infer evolutionary history.

What is a mutation?

change in base sequence of DNA

Harmful vs helpful mutations?

harmful — not passed on , helpful passed on AKA natural selection

Selective breeding

Deciding favorable variations and reproducing them, selectively

Artificial Selection

choosing what organisms will reproduce together

What did Darwin theorize?

Since all the structures are the same, we must come from a common ancestor

What are homologous structures

• structures derived from the same body part of a common ancestor

What is an piece of evidnece of divergent evolution?

homologous structures

When does divergent evolution occur?

when organisms arising from the same ancestral species adapt to different environmental conditions according to the pressures of natural selection.

What are analogous structures?

 same function but do not necessarily come from the same body part and do not indicate a common ancestor

What is convergent evolution?

evolution that has happened from the pressures of environment not common ancestor

Analogous vs homologous structures

Homologous structures share a common evolutionary ancestor and may have different functions (e.g., a human arm and a bat wing), while analogous structures have similar functions but different evolutionary origins, evolving independently to solve a similar environmental challenge

Reproductive Isolation

• ue to one reason or another, part of a species becomes reproductively isolated from another

Examples of reprodcutive isolation

bonobos and chimpanzees

Two effects of reproductive isolation

• no gene flow 

• two seperate gene pools

Definition of biodiveristy

variety of life in an area

what are the levels of biodiversity

ecosystem, species, and genetics

What is the highest level of biodiversity

ecosystem biodiversity

Species biodiversity?

richness and eveness/ number of species in a community

What is the lowest level of diversity 

Genetic Diversity 

Talk about the north island giant moa

hunted to extinction

anthropogenic extintion

what are in situ efforts

Protecting a species in its native habitat.

Ex Situ

Conserving species outside of their natural habita

examples of in situ efforts 

• establishing natural parks 

• rewiliding areas 

examples of ex situ efforts

• zoos 

• seed banks

three main sources of variation

ranfom mutation, meiosis, sexual reproduction

what does meiosis enable in mutations

the production of haploid cells to make gametes

Variation exists fue to what process

random orientation during metaphase I

hello in asexually reproducing populations all memebrs of population are identical

What does meiosis mean in variation?

offsrpidng are varied in allels and random

How does variation promote survival?

• survival of the fittest 

• variation that decrese survival decrease in number 

What is a selective pressure?

external envioronmental factors that influences sucess of individuals in a population

examples of selective pressures

• predation

• disease 

• climate 

When is it called a sexual dimorphism?

Morphological difference between male and female

Intersexual selection

One biological sex chooses which individual of the other sex to mate with

Intrasexual selection

Competition of members of the same sex for access to members of the opposite sex

sexual vs natural selection

• ss is competition for mates while ns is competition for resources 

examples of speciation

darwins finches

grand ranyon squirrels

things that decrease variation in a species 

• stabalizing selection

• genetic drift

• non random mating

allopatric speciation is also the same as

geographic isolation