Properties of life

Levels of organization

Subatomicparticles

atoms molecules organelles cells

tissues

organs

Organ systems

MulticellularORGANISM!populationcommunityecosystem

biosphere

Levels of organization

Subatomicparticles

atoms molecules organelles cells

tissues

organs

Organ systems

MulticellularORGANISM!populationcommunityecosystem

biosphere

Smallest living unit

Prokaryotic vs. Eukaryotic Cells

Prokaryotic EukaryoticPrimitive modernSimple complexDNA is in nucleiod regionDNA is in nucleusNo membrane bound membrane boundorganelles organellesSmaller Larger

Prokaryotic Cell

Eukaryotic Cell

Domains/Kingdoms• Archae: single-celled, prokaryotic, extreme

environments, look like bacteria• Bacteria (Eubacteria): true bacteria, single-celled,

prokaryotic, includes E. coli• Eukarya:

Protista: single-celled plants and animals, eukaryotic, includes Paramecium (pond water organisms)

Fungi: multicellular, eukaryotic, chemotrophs, decompsers, includes: yeasts, molds and mushrooms

Plantae: multicellular, eukaryotic, autotrophs (photosynthesis), includes: grass, shrubs, trees

Animalia: multicellular, eukaryotic, heterotrophs, motile, includes: you!

Prokaryotic vs. Eukaryotic Cells

Prokaryotic EukaryoticPrimitive modernSimple complexDNA is in nucleiod regionDNA is in nucleusNo membrane bound membrane boundorganelles organellesSmaller Larger Bacteria, Archae Protists, Fungi,

PlantsAnimals (Eukarya)

Taxonomy

• Linnaeus/binomial name (Genus species)• Humans = Homo sapiens• Kingdom, Phylum, Class, Order, Family,

Genus, Species• Homology = similarity in structure due to a

common ancestor• Analogy = similarity in function not due to

a common ancestor• DNA comparison

Homologous Structures

Let’s play:Which is more closely related?

• BAT, BIRD, DOG??• BAT & BIRD?• BAT & DOG?• DOG & BIRD?• BAT & DOG!!• WHY??• THEY ARE BOTH MAMMALS (fur and

teeth)

Schools of Taxonomy

• Phenetics: looks for similarity and differences whether homology or analogy

• Phylogenetics/systematics: use homologies to map evolutionary relationship

Phylogenetic tree: series of branches

Energy flow: Food Chain

Grass(producer)

Mouse(herbivore)

Snake(primarycarnivore)

Hawk(secondarycarnivore)

Should this be drawn in a line as above or another shape???

Energy pyramid

What did we leave out??

Grass(producer)

Mouse(herbivore)

Snake(primarycarnivore)

Hawk(secondarycarnivore)

Decomposers (detritivores) = the recyclers!!!

Food Web (multiple food chains)

Energy Flow/Nutrient Cycle

Natural Selection (best adapted survives and reproduces)

Charles Darwin

English Peppered MothExample

Before industrial revolution After industrial revolution

English Peppered Moth Example

Galapagos Ground FinchStudy by Rosemary and Peter Grant

In dry years average beak depth increases-birds with large bills survive better-more large seeds available

In wet years average beak depth decreases-birds with small bills survive better-more small seeds available

Reznick/Endler Study on Guppies

• Guppies in Trinidad (Caribbean)

• Correlated changes in life history characteristics with type of predator

• Small predator (Killifish) preys on juvenile guppies

• Large predator (Pike Cichlid) preys on large sexually mature guppies

• Guppies with cichlids repro at younger age

The Experiment

• Experimental Group: guppies transplanted from pike cichlid to killifish pools

• Control Group: guppies that remained in pike cichlid pools

• What happened??

• Experimental Group/transplanted guppies gained an average of 14% greater mass