how many species exist on earth
7-10 million (some say 100million)
evolution
change over time
descent with modification
all living organisms arose from a common ancestor
Charles Darwin
- developed theory of evolution
- beagle –> Galapagos islands
- wrote on the origin of species
evidence to support evolution
- fossils
- homologies (similarities)
- vestigial structures
- similarities in embryotic development
- DNA/genes/chromosomes
fossils
remains of an organism; imprint of a past organism
-old fossils vs new; similarities but differences
ex: homo erectus–>homo sapiens
ammonite–>natilus
transitional fossils
ex: whale evolved from a land dwelling animal
walking–>walking/swimming–>swimming
homologous structures
organisms with similar structures but different functions
ex: forearm of vertebrates-mammals
vestigial structures
structure that was important for the ancestor but not for descendent.
ex: appendix; whale hind bones
similarities in embryonic development
different organisms that share similarities in their embryonic development
-vertebrates: fish, amphibians, reptiles, mammals
natural selection
process by which evolution occurs.
-those members of a population that possess certain inheritable trait may be best adapted to fit a particular environment
important components of natural selection:
- variation in a population
- heritability of traits
- environmental pressure
ex: DDT–>mosquito = DDT resistant
clade
group of organisms with a common ancestor
taxonomy
classifying and naming living organisms
classification system:
by Carl Linnaeus
- domains
- kingdom
- phylum
- class
- order
- family
- genus
- species
changes in classification- pre 1970s
two kingdoms: plant or animal
changes in classification- post 1970s
Robert Whittaker: five kingdoms: animals plants fungi protists monera (bacteria)
changes in classification- 1890s
Carl Woese:
archaea
bacteria
eukarya- animal, plant, fungi, protist
archaea and bacteria
Domains: archaea and bacteria
cell type: prokaryotic
cell number: unicellular
energy/nutrition: autotrophs and heterotrophs
cell size:
prokaryotic: 1-10Mm
eukaryotic: 10-100Mm
bacteria shapes:
coccus= circular spirillum= spiral bacillus= rod
fiembre
attachment
ribosomes
DNA–>RNA–>Proteins
cell membrane
gate keeper (controls what goes in or out)
cell wall
bacteria has peptidoglycan, archea does not
capsule
(slime layer) attachment; prevents dehydration; prevent phagocytosis
plasmid
contains DNA; antibiotic resistant
flagellum
movement
nucleoid
circular chromosome; haploid
penicillin
first antibiotic ever made–> holes in bacteria
gram staining
crystal violet= purple (thick peptido) (gram +)
safrinin= pink (thin peptido) (gram -)
endospore
resistant/dormant structure (grow into bacteria cells)
binary fission
asexual reprouction
photo=
sunlight for energy
chemo=
chemicals for energy
extremophiles
extreme environments
ex archaea
thermophile
loves heat
psychrophile
loves cold
acidophile
loves acid
alkaliphile
high plt
barophile
high pressure
halophile
salt
benefits of bacteria/archaea
- digestion
- normal flora
- nitrogen fixation
- gene therapy/ bioengineering
- antibiotics
- decomposers
- bioremediation
- primary producer
- biofuels
- food
protists
domain: eukarya kingdom- protists cell type- eukaryotic cell #- mostly single energy/nutrition: autotroph- photosynthesis: plant heterotroph- absorption: fungi heterotroph- ingestion: animals
fungi-like protists
heterotrophs- absorption and decomposition
- water molds
- slime molds
water molds
unicellular
ex: downy mildew, late blight
plasmodial (acellular) slime mold
mass of cytoplasm surrounded by cell membrane
-multi nuclei
cellular slime mold
individual cells
plant-like protists
autotrophs- photosynthesis
- algae
- phytoplankton: single celled (70% of photosynthesis)
- seaweed: multicellular
dinoflagellates
photosynthesis- coral reefs
red tide- massive growth
diatoms
(fresh water)
silica shell
Euglena
(fresh water)
single celled plant-like protists
brown algae
(salt; temperate ocean)
- multicellular
- can grow up to 6 in a day
ex: kelp (make photosynthesis)
red algae
(salt; tropical ocean)
- multicellular
- photosynthesis
ex: -nori- sushi - agar- solid surface to grow bacteria (used in microbiology)
- carrageenan- makes icecream thicker
green algae
(fresh water)
- single or multicelled
- plants come from
- photosynthesis
animal-like protists
heterotrophs- ingestion
protozoa
animal like protist
pseudopods
- amoeba
- foraminiferans- calcium carbonate for a shell
- radiolarians- silica shell
flagella
- African sleeping sickness
- contaminated water
ciliates
- cilia (how they move)
- paramecium
study of fungi
mycology
fungi
domain- eukarya kingdom- fungi cell type- eukaryotic cell #- multicellular energy/nutrition- heterotrophs- absorption; decomposition
mycelium
network of filaments
hypha-filament
one cell thick
fungus cell wall
contains chitin
reproduction of fungi
- asexual: mitosis and meiosis
- sexual: more diversity; produce spores
five groups of fungi
- chytridomycota
- zygomycota
- glomeromycota
- Ascomycota
- basidiomycota
chytridomycota
- aquatic environment
- flagellated spores
- organic waste
ex: batrachochytrium- killing frogs
zygomycota
- sexual reproduction to produce zygospore
ex: black bread mold; dung-fungi
saprobes
lives off of dead organisms
glomeromycota
- relationship with plants
- fungi+plant roots– 80% land plants
ascomycota
-ascus- sac
ex: morels
truffles- (by roots of oak tree)
yeast
penicillin
blue cheese
athletes foot
basidiomycota
basidia- club=spores ex: mushroom, puffball, shelf fungi corn smut
Streptococcus pneumoniae
pneumonia
Bacillus anthracis
anthrax
Escherichia coli
E coli
Borrekua burgdorferi
lime disease
Treponema pallidum
syphilis
Streptococcus pyofene
strep throat
Streptococcus mutans
plaque
Clostridium botulinum
botulism
Clostridium tetani
tetanus
Staphylococcus aureus
toxic shock syndrome; staff infection
Helicobacter pylori
ulsers
Plasmopara viticola
downy mildew- grapes
Plytophthora infestans
late blight- potatoes
Pfiesteria piscicida
killed more than 1 billion fish
Karenia brevis
toxic- clams, mussels, oysters
Entamoeba histolytica
amoebic dysentery (sick because of contaminated water)
Trypanosoma bruci
African sleeping sickness
Plasmodium falciparum
malaria
Tocoplasma gondii
toxoplasmosis (in cat feces; bad for prego women)
Rhizopus stolonifer
black bread mold
Pilobolus species
dung fungi
Candida albicans
yeast infection
Penicillum chrysogenum
penicillin
Claviceps purpurea
ergotism (in rye bread) –> LSD
Armillaria osyoyae
biggest mushroom found in Oregon
Amanita phalloides
death cap- fatal