Ch 25/26 Prokaryotes Flashcards
3 types of prokaryote shapes
Spherical - cocci
rod - bacilli
spiral - spirillium
Characteristics of Prokaryotes
no nucleus
- have peptidoglycan layer
4 possible external structures of prokaryotes
Capsule - surrounding the cell wall
Biofilms(plaque on teeth), embedded in slimy matrix
Pili - protein structures extending from cell
- sex pili transmit DNA
Flagella - moves different compared to eukaryotic (propeller)
Heterotroph
(other feeder) get energy and carbon from other organisms
autotroph
(self feeder) make own energy from inorganic material
2 types of heterotrophs
Chemo heterotrophs: most common, includes decomposers and pathogens
photo heterotrophs: obtain carbon from other organisms, cant use CO2, have photosynthetic pigments
2 types of Autotrophs
Chemo: get energy by oxidizing inorganic chemicals such as amonia (near hydrothermal vents)
Photo: get energy from the sunlight, includes cyanobacteria
Aerobic Bacteria
require oxygen for cellular respiration
EX: bacillus spp (common in soil and spoiled foods)
facultative anaerobes and example
doesnt have to have oxygen but can use it when needed
EX: E. coli
Obligate anaerobes
grows with NO Oxygen
EX: Bacteroides ( main thing in mammal gut, makes methane)
3 types of Asexual reproduction
1) Binary fission - cell divides forming 2 cells(most common)
2) Budding - bud forms and separates from mother cell
3) fragmentation - walls form inside cell and they can seperate into multiple cells
genetic material exchange
Transformation
bacterial cells pick up fragments from other cells
genetic material exchange
Tansduction
bacterial phage carries DNA from one cell to another
genetic material exchange
Conjuation
2 cells connect to each other and exchange genetic material
gram positive bacteria wall and stain color
has very thick peptidoglycan wall
Purple stain
gram negative bacteria and stain color
have thin peptidoglycan layer and an outer plasma layer(membrane)
Pink(red) ?
Gram- Positive: Actinomycetes
what do they resemble, why are they significant
resemble fungi
- several produce antibiotics such as streptomycin
Gram-Positive: Lactic acid bacteria
why is it significant
inhabit decomposing plant material and milk, make Yogurt
Gram-Positive: Streptococci
where and what do they do
inhabit mouth and digestive tract of humans and animals
- some cause strep throat
Gram-Positive: Staphylococci
where and what are they
live in nose and on skin
- opportunistic pathogens
Gram- Negative: examples
- Rhizobium in roots of legumes
- arthropod bites/ excretions
- typhus, Rocky Mountain spotted fever
- chlamydias
Gram-Negative: Cyanobacteria 3 characteristics
- important photosynthesizes
- prokaryotes with cell specialization
- have Heterocyst (special oxygen excluding cell for nitrogen fixation)
Who rejected the hypothesis that spontaneous generation can occur
Louis Pasteur
3 types of Archaea and their environments
1) Methanogens - produce methane from carbon. live in anaerobic environments
2) Extreme Halophiles - in saturated salt solutions (Great Salt Lake and Dead Sea)
3) Extreme Thermophiles - live in extreme temps such as deep sea vents
- No/few known pathogens
Symbiosis: 3 types
1) Mutualism - both benefit
2) Commensalism - 1 benefits and the other isn’t effected
3) Parasitism - parasite benefits and host harmed
heterocysts
special oxygen excluding cell for nitrogen fixation
exotoxins
strong poisons released by pathogenic bacteria
endotoxins
poisonous components of cell walls released when bacteria dies
R factors
plasmids with genes for antibiotic resistance
mitosis
division of the nucleus without chromosome reduction
mieosis
nuclear division leading to chromosome number reduction
4 types of protists body types
1) unicellular - most protists
2) collonies - loosely connected groups of cells
3) coenocytes - multinucleate masses of cytoplasm(one big cell)
4) multicellular organisms ( some giant)
