Chapter 27 Flashcards
__________________ were the first forms of life on earth. all organisms can trace their ancestry back to these organisms
prokaryotes
prokaryotes are ____________________ everywhere
incredibly abundant
-there are more organisms in ones mouth than have ever lived
all prokaryotes are ___________________________
unicellular, though they aggregate in colonies
_____________ is an assemblage of unicellular organisms that do exist (permenately or temporarily) as a multicellular unit, though there is no division of labor and each organisms could live independently
colonies
_______________ are colonies of prokaryotes held together by a sticky extracellular matrix. They can adhere to many surfaces
biofilms
cell size of a prokaryotic cells
1-5 picometers in diameter where as eukaryotic cells are 10-100 picometers in diameter
the shapes of prokaryotic cells
- coccus
- bacillus
- spiral
spherical shaped cells
coccus
rod shaped cells
bacillus
strepto means
a colony in a chain
staphylo means
a colony in a cluster
______________ is an external to the plasma membrane
cell wall
bacteria cell walls are made of
the polysaccharide peptidoglycan
bacteria have cell walls with many layers of peptidoglycan
gram positive
bacteria have cell walls with fewer layers of peptidoglycan but with an outer phospholipid membrane
gram negative
____________________ are made of a variety of polysaccharides and polypeptides but no peptidoglycan
archaea cell walls
is external to the cell walls in some prokaryotes
capsule
certain prokaryotes possess flagella for
locomotion
prokaryotic flagella are different in composition than
eukaryotic flagella
___________ is embedded in the cell wall and plasma membrane in a prokaryotic flagella
basal apparatus
_______________ acts as a motor that rotates the flagellum propels the cell
basal apparatus
a single circular DNA molecule called the prokaryotic chromosome is dispersed throughout
the nucleic region of the cell
-no membrane or nucleus
______________ proteins are not associated with a bacterium’s chromosomes but they are present in archaea
histone
____________________ are small separate rings of DNA
plasmids
Plasmids consist of ______________ genes
plasmid genes are often not necessary for survival but can provide survival advantages
only a few genes
____________________ in the cytoplasm function for protein synthesis
ribosomes
infolding of the ________________ functions in the photosynthesis and or cellular respiration
plasma membrane
prokaryotes reproduce asexually by __________
binary fission
the prokaryotic chromosome replicates, followed by division of the cell
each new cells receives a copy of the chromosomes
prokaryotes can divide by binary fission at extremely fast rates
-a typical generation time is 2 hours/ Some generation time can be as short as 20 minutes
_____________ are responsible for most of the genetic variation in prokaryotes
mutations
three forms of genetic recombination
- transformation
- transduction
- conjugation
dead decaying prokaryotes release DNA segments (genes into the eviroment which, can then be taken up by prokaryotes
transformation
viruses that infect prokaryotes can transfer DNA segments (genes) from one prokaryote to another
transduction
a prokaryote can directly transfer DNA (a plasmid) to another prokaryote
conjugation
_________________ is a hesitant structure that surrounds the prokaryotic chromosome during harsh environmental conditions
endospore
During harsh environmental conditions, the endospore causes the
metabolism halts and rest of cell disintegrates
prokaryotes can live dormant for year as
endospores, they reactivate when conditions improve
many prokaryotes are ________________ similar to animal and fungi, however some are _________________ like plants
heterotrophic
autotrophic
earths first photosynthesizing autotroph
cyanobacteria
other prokaryotic autotroph that obtain energy from chemicals
chemotrophs
_____________ acquiring oxygen for cellular respiration
obligate aerobes
____________________ do not require oxygen for fermentation and they are poisoned by oxygen
obligate anaerobes
________________________ they use oxygen for cellular respiration if its present and fermentation if not
facultative anaerobes
_____________________________They convert atmosphere nitrogen gas to ammonia and other usable forms that allow the nitrogen to be incorporated into proteins and nucleic acids. Larger animals are dependent upon this
some prokaryotes fix oxygen
cyanobacteria that nitrogen fix and posses heterocytes the most self sufficient organisms on earth
heterocytes
_________ of all human disease are caused by bacteria
half
___________________ results in 1.5 million deaths a year. Example of disease caused by bacteria
tuberculosis
the most common ___________________ in the us is bacterial
vector borne disease
vector borne disease transmitted by ticks
lime disease
bacteria are pathogen due to _________________
poisons in their cell walls
______________________ are secreted by living bacteria
exotoxins
_____________________ are released when a bacterium dies and its cell wall breaks down
endotoxins
______________ attack bacteria cell walls or the ribosomes that make the bacteria cell wall
antibiotics
bacteria ____________ fix for other organisms
nitrogen
__________ produce oxygen and serve as base of food chain
cyanobacteria
prokaryotes are the main ____________________ in all ecosystems
decomposers
only a small fraction of prokaryotes species are __________________
pathogenic
trillions of prokaryotes reside in ________________
human intestine and digestive tract, they digest food that we would otherwise be unable to digest
_______________________________ by prokaryotes produce cheese yogurt pickles and salami
lactic acid fermentation
__________________ is the use of organisms to degrade environmental pollutants
biomediation
examples of prokaryotes being used for biomediation
- sewage treatment
- oil clean up
an efficient way to produce large quantities of human, other animal, or plant proteins by inserting genes into prokaryotic plasmid DNA to rapidly replicate
recumbent DNA biotechnology
the traditional classification of prokaryotes was based on the _____________________
morphological characteristics
ex- shape, cell wall, mode
modern classification shows that tradition classification does not produce try
clades
the current classification is based on ____________
molecular characteristic
__________________ have been replaced by groups that now more accurately represent phylogeny
tradition groups
there are more similarities between archaea and ______________ than between archaea and ______________
eukarya
bacteria
____________ are gram negative spiral shaped bacteria. Certain spirochetes are parasitic.
What two disease do they cause
Spirochetes
Lyme disease and Syphalsis
______________ the smallest bacteria group. they are gram-negative and cocci. They are entirely parasitic and is the cause of the common bacterial sexual transmitted disease _______________.
chlamydias
chlamydia
important decomposers in the oil. Mycobacterium cause tuberculosis and commonly acne
bacilli high GC gram positives
unicellular or colonial, gram negative, aquatic, photosynthetic anabaena fixes nitrogen
cyanobacteria
type of cyanobacteria that fixes nitrogen
anabaena
mounds of cyanobacteria within densely packed sediment, found in warm shallow bays
found in warm shallow bays
abundant in fossil record
stromatolites
___________________ cause staff infections, sepsis, and
staphylococcus
causes strep throte
streptococcus
ferments in milk and yogurt, cause staff infections and strep infections
Low GC gram positives
______________ is the cause of botulism and tennisunlike bacillus anthraces is the cause of anthrax
clostridium
clostridium and anthraces are examples of
endospore forming
gram negative, epsilon proteobacteria. helicon pylori causes ulcers. is the most common nitrogen fixers bacterium within root nodules. closely related to eukaryotic mitochondria
proteobacteria
important for nitrogen fixing.bortella purtusis causes whooping cough and neisseria gonorrhoeae causes sexually transmitted disease gonorea. Can also cause cholera, salmonella, and influenza pneumonia
proteobacteria
types of protea bacteria
- epsilon
- alpha proteobacteria
- beta proteobacteria
- gamma proteobacteria
originally believed to be restricted to extreme habitats, extremophile. They are also known to inhabit almost all environments on earth they are not known to be parasitic
archaea
________ they are not known to be parasitic
archaea
word for archaea
extremophiles
two types of archaea
- crenarchaeota
- euryarchaeota
__________ have two extreme thermophiles in _________________
crenarchaeota
hot springs- hot acidic environments
hydrovents- hot and high pressure environments
extreme halophiles and methanogens
euryarcheota
high salty environments, salty seas and lakes.
extreme halophiles
obligate anaerobes in swamy marshes and cattle
methanogens
cattle produce __________ by metabolic process to release waste
methane