chapter 6 Flashcards
describe heterotrophs.
a heterotroph is an organism that must obtain its carbon in an organic form.
describe autotrophs.
an autotroph is an organism that uses inorganic CO2 as its carbon source.
what are phototrophs?
microbes that photosynthesize (create energy from sunlight)
what are chemotrophs?
microbes that get their energy from chemical compounds.
photoautotrophs
are photosynthetic, captures the energy of light rays and transform into chemical energy that can be used in cell metabolism.
chemoautotrophs
are of two types; chemo organic autotrophs –use organic compounds for energy and inorganic compounds as a carbon source.
lithoautotroph
type of chemoautotroph; requires neither sunlight nor organic nutrients; relies solely on inorganic minerals.
chemoheterotrophs
derive both carbon and energy from organic compounds. these microorganisms belong to both saprobes and parasite to obtain their organic nutrients.
saprobes
occupy as decomposers of plant litter, animal matter, and dead microbes.
parasites
live in or on the body of a host
endoparasites
parasites which live in organs and tissues
ectoparasites
parasites which live on the body externally
pathogen
another term for a parasite; cause damage to tissues (disease) or even death
intracellular parasites
parasites which live within cells and are the most extreme type.
obligate parasites
parasites which are unable to grow outside of a living host
diffusion
the process by which atoms or molecules move in gradient from an area of higher concentration to an area of lower concentration.
osmosis
diffusion of water through selectively permeable membrane
isotonic solutions
have a tonicity that is the same as the body’s plasma. when administered, there will be very little movement, if any, between the body tissues and the blood vessels.
hypertonic solutions
have a tonicity that is higher than the body plasma. when administered it will cause water to shift from the extravascular spaces into the bloodstream to increase the intravascular volume–this is how the body attempts to dilute higher concentration of electrolytes in the IV fluid
hypotonic solutions
have a tonicity that is lower than the body plasma, causing water to shift from the intravascular to extravascular space, and eventually into the cell tissues–in this case, the body moves water from the intravascular space to the cells in order to dilute electrolytes in the cells.
transport
the process of moving molecules in or out of a cell
active transport
transports nutrients against the diffusion gradient or in the same direction as the natural gradient , but that a rate faster than by diffusion alone
endocytosis
the process by which substances are carried into the cell, cell encloses the substance in its, membrane and at the same time, it forms a vacuole and engulfs it.
phagocytosis
a form of endocytosis in which amoebas and certain white blood cells ingest whole cells or large solid matter. CELL EATERS
pinocytosis
a form of endocytosis and is the process
pinocytosis
a form of endocytosis and is the process in which liquids, such as oils or molecules in solution, enter the cell. CELL DRINKING
three cardinal temperatures
temperatures for the growth of a given microbial species minimum temperature
maximum temperature
optimum temperature
minimum temperature
the lowest possible temp. at which a microbes growth and metabolism is permitted
maximum temperature
the highest possible temperature at which a microbes growth and metabolism is permitted.
optimum temperature
small temp. range – between minimum and maximum
promotes fastest rate of growth and metabolism
obligate arobes
requires air
microaerophile
less air. microorganisms that require less air
obligate arobes
requires air. humans we need air!
acidophiles
organisms that thrive in acidic environments
alkalinophiles
organisms that thrive in alkaline (basic) environments
osmophiles
live in habitats with a high solute concentration.
halophiles
halo = salt. osmophile that prefer concentrations of salt.
barophiles
deep sea microbes that are adapted to high pressure environments
essential nutrients
any substance that must be provided to an organism
symbiosis
organisms live together, think partnership
mutualism
both organisms’ benefit.
commensalism
one benefits, one is left alone.
parasitism
one benefits, one is harmed
non-symbiotic relationship
when organisms are not together – no partnership
synergism
organisms work together and share nutrients
antagonism
organisms harmed by others
binary fission
one parent cell becomes two daughter cells
lag phase
inoculation occurs, cells begin to multiply.
log phase
exponential growth
stationary phase
when growth is consistent
death phase
when bacteria dies and no more growth
long term stationary phase
dormant– microorganisms will not grow
psychrophile
bacteria prefer cold, thriving at temperatures below 15 degree celciums
mesophiles
meso, middle, moderate, bacteria that grow in MODERATE temperatures.
thermophiles
bacteria grow in HOT temperatures greater than 40 degrees.
neutrophiles
bacteria likes neutral environments
