1. Unit 8 Study Guide
Test: 2/27/17

2. Classification/Taxonomy
Binomial nomenclature
What is a taxon (or taxa)? A group of organisms that are grouped together because of relatedness Can you list the levels of taxonomy in order from most specific to least specific? Species, Genus, Family, Order, Class, Phylum, Kingdom, Domain Downsides of Linnaean classification in the past? Based on only physical appearance, no other forms of evidence were known How many domains are there? 3 – Archaea, Bacteria, Eukarya What makes the domains different from each other? Bacteria – single celled, prokaryotic, Archaea – single celled, prokaryotic, tough exterior Eukarya – multi/single celled, eukaryotic

3. Origins of life
How old is earth estimated to be? How old is life on earth? Earth: 4.5 billion years old; Life: 3.5 billion years old What did the Miller-Urey experiment discover? That early building blocks of life (amino acids) can be created from Earth’s early atmosphere with no oxygen What is endosymbiotic theory? Theory that support the claim early life was prokaryotic and eukaryotic cells were formed by combining different prokaryotic cells

4. Darwin’s early work
What did Darwin mean by “variations”? Differences of similar organisms from one another. (beak size, height, shape, color) Do you know what catastrophism, uniformitarianism, and gradualism are? Catastrophism – changes in Earth/living things from natural disasters Uniformitarianism – changes are at a consistent rate Gradualism – changes occur very slowly over time What does it mean if a species has high fitness? It is likely to survive and pass on inheritable traits to offspring that can do the same Define natural selection When the most beneficial traits are passed on in successive generations

5. Darwin’s early work
What factors contribute to natural selection? Descent with modification, Overproduction, Adaptations, Competition What are populations? Number of species in a given area What are adaptations? Changes made that help are organisms better survive it’s surroundings What is artificial selection? When humans cater what traits will be passed on in future generations

6. Evidence of evolution
What are homologous structures? Structures that are similar in design but different in function – show relatedness What are vestigial structures? Structures that are unnecessary and “left over” from evolution – show links in distantly related organisms What are analogous structures? Structures that are different in design but similar in function – show they are not closely related

7. Evidence of Evolution
How do the following support the theory of evolution?
Fossils –
Give a relative date for how old organisms are – compare change over time
Biogeography –
distribution of organisms over areas over time might show relatedness
Embryology –
comparing embryos of different organisms – look more alike, likely more related
Molecular evidence –
DNA/amino acid/protein analysis shows how close organisms are related by comparing similar sequences among millions of combinations
Direct observation –
has been seen in person by scientists (example: antibiotic resistance)
Comparative anatomy –
comparing body parts to one another (homologous/analogous/vestigial structures)
Molecular evidence is the most accurate form of evidence

8. Mechanisms of evolution (other than natural selection)
What is gene flow? The movement of organisms into new populations to move in new traits What is genetic drift? Random chance events eliminate traits due to events that cause loss (disease, disaster, predation) Natural selection Olson’s a dummy – cross this out Mutations Random changes in DNA sequence causing new phenotype

9. Hominid Evolution
a. How do today’s humans differ from the most recent common ancestors? i. Skull size – todays humans have a large skull ii. Jaw size – today we have a smaller jaw iii. Digestive tract – less complex - shorter, process variety of foods iv. Language development – Humans have written and spoken this v. Tools/fire usage – Large brain = making important developments