Guided Notes: Evolution

Guided Notes: Evolution

The Theory of Evolution

How Have Organisms Changed?

The Endosymbiotic Theory:

The ______proposes that eukaryotic cells arose from living communities formed by prokaryotic organisms.
~2 billion years ago - ______of internal membranes in ______
The result was the ancestor of all ______cells.
Endosymbiotic Theory: Eukaryotic cells formed from a______among several different prokaryotic organisms
Prokaryotes that use oxygen to generate energy-rich molecules of ATP evolved into ______
Prokaryotes that carried out photosynthesis evolved into ______

Evidence of Evolution

Fossil Evidence: ______show us the similarities between organisms of the past and present
______describe similarities between the anatomical structures of species
______are anatomical structures that still appear, but are no longer used!
Examples: ______
Suggests that these structures may have existed at a previous time or in an ancestor; organisms evolved and structures

Comparative Embryology: Insects and animals often have very similar ______development
Ex. ______
Suggests a ______

Biochemical Evidence: Comparison of ______and macromolecules between organisms
Through ______
Tells us what organisms are closely related

Evolution and Natural Selection

______is best known for his contributions to the theory of Evolution
On a five year voyage on a ship called the Beagle, Darwin recorded his observations of ______he found along the way
This led Darwin to develop the idea of ______and ______
______means that those organisms best adapted to their environment will survive, reproduce, and ______
“Fittest” means______, not strongest!

Adaptation: Any ______trait an organism has that helps it to ______
If an organism does not have adaptations to best fit its environment, it will die
“Survival of the Fittest”
Example: Bird beaks-Imagine that birds had different sized beaks in an area where the food source was seeds. In order to crack them, the birds needed a large, strong beak. Which would survive and reproduce?

Species have the potential to increase ______, but environmental factors maintain lower population numbers
Resources required to sustain ______
______conditions
Relationships among organisms in ______

Changing environments select for specific ______
Those organisms with favorable ______survive, reproduce, and pass on their ______to future generation
Over time, the accumulation of favored alleles leads to a change in ______
(change over time = evolution)

Case Study: Antibiotic Resistance

Organisms are constantly changing and adapting; ______reproduce and evolve quickly to adapt to constant changes!
Humans often use ______to combat harmful bacteria (ex. Staphylococcus)
Some bacteria are born with a ______resistance (an adaptation!) to the antibiotic
These bacteria will ______and ______, creating a group that are resistant to the drugs

Other Disease Agents in Natural Selection

Passive Immunity: Immunity to certain diseases is given from ______to ______at birth
Continued through antibodies passed through ______

Active Immunity: Immunity acquired through exposure to a ______
After exposure, your body builds up an ______
______allow you to artificially gain an active immunity without exposure to the actual disease

Causes of Variation

Genetic Recombination: Dominant and Recessive alleles in genes, along with polygenetic traits and complex genetics, lead to individual organisms with different ______(and thus, adaptations)

Mutations: Changes in DNA sequences can introduce both good and bad new ______into a population (ex. Immunities, resistant bacteria, pesticide resistant plants)

Speciation

Geographic Isolation

When mountains, islands, etc. keep a population ______
Species will meet different environmental challenges, change and evolve ______than the ______population
Geographic Isolation leads to ______, when one species evolves into many different species over time due to competition of habitat or food!

Variation

Coevolution

Genetic Drift

The change in a______of a gene variant (allele) in a population due to random ______
Due to a random event, a ______happens to the organisms in a population
Much more frequent in ______populations!
Example:
Founder Effect
Bottleneck Effect

Classification Systems

Classification systems are how we ______organisms
This is called ______
The classification of organisms has changed and evolved over the years due to new ______
Greater understanding of evolutionary relationships, thanks to ______, has allowed for more detailed classification
The classification of organisms begins with the______groupings and moves down to the ______(domain species)
The classification order is as follows:

__________________________________________

Scientific Name: The scientific name of an organism is the______and______of an organism
Always written in ______
Example: Humans are Homo Sapians
Only species are able to ______!

Case Study: Interbreeding
Only species are able to interbreed. Organisms of two different species normally will not ______
Sometimes, organisms within the same genus are able to ______, but the offspring are not ______(they cannot reproduce!)
Example: ______
These hybrid organisms are much more common in captivity than in the wild

Dichotomous Keys

A key that helps ______an organism
Uses ______to lead you to the ______of an organism
By looking at features of an organism, the key will help you determine what it is!

Phylogenetic Trees