Bacteria Flashcards
– include organisms that have a prokaryotic cell that lacks a nucleus (nonexistent kingdom that divides into the domains Archaea and Bacteria)
monera
bacterial species that produce their own nutrients through the process of photosynthesis, using CO2 from the environment
photoautotrophs
bacteria that perform photosynthesis but cannot use CO2 from the environment
photoheterotrophs
get their energy from inorganic compounds, and their carbon needs are obtained from CO2
chemoautotrophs
energy is obtained from inorganic substances but carbon can’t be obtained from CO2
chemoheterotrophs
some bacteria are – since they always require oxygen for aerobic cellular respiration
obligate aerobes
never need oxygen, generally not dividing, can be killed by exposure to oxygen
obligate anaerobes
require oxygen sometimes
facultative anaerobes
circular in shape
cocci
pair cocci
diplo
cluster cocci
staphyl
chain cocci
strepto
rod or oblong shaped; they may occur in chains
bacilli
spiral shape
spirilli
genome is located in cytoplasm in a region called – and is not bound by a membrane
nucleoid
bacterial genome usually consists of a single, circular piece of DNA that does not contain many – as opposed to eukaryotic cells
introns and exons
bacterial envelope consists of the cell membrane, –, cell wall, and outer membrane
periplasm
cell envelope consists of a cell membrane and thick wall of peptidoglycan
gram-positive
envelope consists of a thin cell wall made of an outer membrane and peptidoglycan, periplasm, and inner plasma membrane
gram-negative
space between the inner and outer membrane
periplasm
cell wall is made of peptidoglycan (–) which is a polymer of disaccharides that are crossed linked with a chain of 4-6 amino acids
murein
disaccharide of peptidoglycan is composed of repeating units of N-acetylglucosamine and N-acetlmuramic acid, and the latter will form an – link with the short chain of amino acids
amide
peptide – will form between two neighboring peptide chains, allowing the cell wall to increase in thickness as these – form between other neighboring peptide chains as well
cross-bridge
common target of antibiotics such as penicillin and vancomycin is preventing the proper synthesis of the –
cell wall
gram negative cells contain an extra membrane in addition to the plasma membrane
outer membrane
face of the outer membrane that is pointed to the interior of the cell will contain – that are attached to the cell wall
lipoproteins
face of the outer membrane that is pointed to the exterior of the cell will contain – which are lipids attached to polysaccharides
lipopolysaccharides (LPS)
LPS are – and are not harmful so as long as they are part of the cell
endotoxins
if the cell ruptures and LPS are released they will begin to – the immune system of the host
overstimulate
space contained within the plasma membrane of the cell
cytoplasm
protein synthesis
ribosomes
contain the genes needed to produce proteins
chromosome
some bacterial cells contain small additional loops of DNA called – (often contain genes coded for resistance)
plasmids
layer of sugars and proteins on the outer surface of some bacterial cells
capsule
forms a sticky layer that can help the cell attach to surfaces and can help keep bacterial cells from being phagocytosed
slime layers
bacteria with one or more flagella are motile as the flagella – to propel the cell
rotate
T/F: bacterial flagella are different from eukaryotic flagella in structure
true
bacterial flagella consist of the protein – in a hollow, helical conformation that anchors into the cell membrane
flagellin
a – in the membrane provides power to rotate each flagellum
proton pump
– are tiny proteins that generally cover the surface of some types of bacterial cells
pili
pili assists the cell to – to surfaces
attach
few species are capable of creating – when environmental conditions re not favorable
spores
when conditions become favorable again, the spores germinate into the – again
vegetative cell form
T/F: bacteria lack a nucleus an so cannot perform mitosis
true
replication of a single loop of DNA, a copy of which is then provided to each of two daughter cells
binary fission
binary fission can occur fairly quickly, in some cases as often as once every – minutes
20
because bacteria are unicellular, creating a new cell means creating a new organism so binary fission qualifies as – reproduction as each division produces genetically identical offspring
asexual
ways to introduce variation into a population is by –, conjugation, transduction, and transformation
mutation
during – one bacterial cell may copy its plasmid to be passed to another cell
conjugation
in order to pass a plasmid to another cell a physical connection called – must be made by the cell that contains the plasmid
sex pilus
lacks plasmid
female (F-)
has plasmid
male (F+)
occasionally plasmids become integrated into the chromosome which is termed – and when the plasmid is transferred via conjugation, some of the bacterial chromosomes may be transferred as well
Hfr chromosome
some bacteria are resistant to multiple – as a result of picking up several plasmids via conjugation
antibiotics
some bacteria pick up DNA from their environment and incorporate it into their own chromosomal DNA
transformation
regulation of bacterial gene expression is primarily by –
operons
operons controls the access of RNA polymerase to the genes to be transcribed primarily via –
repressor proteins
– on the DNA where RNA polymerase must bind; if it is not accessible, the gene will not be transcribed
promoter sequence
– on the DNA where a repressor protein can bind, if present
operator sequence
when a – is bound to the operator, the promoter sequence will be blocked such that RNA polymerase cannot access the site
repressor
– produces a repressor protein when expressed
regulator gene
actual genes being regulated by the operon
structural genes
– operons are normally off
inducible
– operons are normally on
repressible
in an inducible operon, the repressor always bind to the operator so that – is always prevented unless an inducer molecule is present
transcription
when the – is present, it binds to the repressor, preventing the repressor from binding to the operator
inducer
in repressible operon systems, the repressor is always – such that transcription always occurs
inactive
in repressible systems, only when a – is present to interact with the repressor can transcription be inhibited
corepressor
when the repressor and corepressor are bound, they can then interact with the operator site and prevent access by – thus turning off transcription
RNA polymerase
bacteria have a typical growth cycle that is limited by – as well as the amount of nutrients available
environmental factors
there is an initial, usually brief – in growth that occurs when a new population of bacteria begins to reproduce
lag
as bacteria begin to perform binary fission at a very rapid rate, – growth occurs
logarithmic
T/F: logarithmic growth can only last for a limited amount of time
true
as the number of bacteria increase, resources such as food and space decrease, and while some bacteria are still dividing, some are dying, which evens out the population count
stationary phase
as the pop hits its max, the lack of nutrients, along with the presence of toxins, means that the pop will begin to –
decline
when the pop begins to decline, the few species capable of making – will do so at this point
spores
