Exam 1 Flashcards
taxonomy
classification of living organisms based upon relationship
2001: All species inventory
1.7 million organisms identified, 100 million species unknown(know least about bacteria)
How are all cells alike structurally
- dna is genetic material
- cytoplasmic membrane
- reproduction
- cytoplasm
- ribosomes
phylogeny
study of evolutionary relatedness
DNA similarity especially prokaryotes
5 kingdoms
Animalia Plantae Fungi Protista Monera or Prokaryote
Domain System
proposed by Carl Woese based upon ribosomal sequence
Bacteria
Mitochondria, Proteobacteria, gram positive bacteria, thermotoga, cyanobacteria, chloroplasts
prokaryotic, peptidoglyca, 70S
Archaea
Methanogens, hyperthermophile, extreme halophiles
prokaryotic, no peptidoglycan, 70S
Eukarya
animals, fungi, amebae, slime molds, plants, green algae,euglenezoa, distoma, dinoflageflates, ciliates
eukaryotic, varies, 80S
Endosymbiotic Theory
early cell--> bacteria -->chloroplast --> mitochondrion -->archaea -->eukarya able to create more ATP
How do we know that mitochondria and chloroplasts were bacteria?
Own genetic material-circular chromosomes, suggests was once living cell
70S ribosomes
Multiple membranes, suggests cell has been eaten
How do we know this happened?
Earth 4.6 billion years old
prokaryotes 3.5 billion years(more diverse)
eukaryotes 2.5 billion years
Scientific Nomenclature
Genus species(italicize)
Domain
Bacteria, Archaea, Eukarya
Eukaryote
group of closely related organisms that can interbreed
Prokaryote
population of cells with similar characteristics, dont reproduce sexually
unsure how to organize prokaryotes
Viral Classification
not composed of cells
a population with similar characteristics that occupy a particular ecological niche(host))
Origin of Virus
Replicating strands of nucleic acid
Degenerative Cells
coevolved part of host cell
Cell Theory
all living things are composed of cells
Theory of spontaneous generation
Francisco Redi, Lassaro Spallanzani
production of living organisims from non-living matter
Theory of Biogenisis
Rudolf Virchow
life comes from life
Louis Pasteur
disproved spontaneous generation theory with swan neck flask, took 200 years
found: microbes are present on non-living things, microbes can be destroyed by heat, airborne contamination can be obstructed
golden age of microbiology
1800s
Germ Theory
Fracastoro
Germs are causative agent of disease
something indivisible passed from person to person
different that traditional beliefs
Ignaz Semmelweis
Hand washing to prevent childbirth fever