DETAILED ANSWERS|LATEST
UPDATE!!!2025/2026|GUARANTEED PASS|GRADED
symbiotic relationship - ANSWER two organisms live together in a close partnership. at
least one person in the relationship benefits
mutualism - ANSWER obligatory, dependent, both members benefit
commensalism - ANSWER commensal member benefits, the host is not harmed but
does not benefit
parasitism - ANSWER parasite is dependent and benefits, hosts is harmed
3 types of symbiotic relationships - ANSWER mutualism, commensalism, parasitism
non-symbiotic relationship - ANSWER organisms are free living, relationships *not*
required for survival
syntropy - ANSWER communal feeding between organisms in a shared habitat
antagonism/amenalism - ANSWER actions of one organism affect the success of
survival of others in the same community (AKA competition)
2 examples of non-symbiotic relationships - ANSWER syntropy, antagonism/amenalism
1
,action of amenalism - ANSWER can produce toxic substances that inhibit the growth
of other bacteria
how do biofilms communicate? - ANSWER quorum sensing
biofilms - ANSWER result when organisms attach to a substrate by some forming an
extracellular matrix that binds them together in complex organized layers
what dominates the structure of most natural environments on earth? -
ANSWER biofilms
where are biofilms found? - ANSWER both artificial and natural surfaces
biofilm formation steps - ANSWER reversible attachment, irreversible attachment
(quorum sensing), microcolony, mature biofilm, dispersal.
function of matrix - ANSWER allows cells to adhere to each other and to the surface
what happen when a cell loses its flagella? why is this important in biofilm formation? -
ANSWER lose motility and then the biofilm forms. the cells do not need to be mobile,
they are going to stay put in the biofilm, so flagella are not needed
microcolony - ANSWER biofilm beginning to grow in size. first maturation stage
mature biofilm - ANSWER complex biofilm structure, cells diversify, cell growing,
continues to mature
dispersal - ANSWER black and white cells, some with flagella, biofilm can now open
up, free living cells can now leave and form new micro-colonies to make more biolfims
2
, reversible attachment - ANSWER cells attach and detach from the surface
irreversible attachment - ANSWER cells multiply and start producing biofilm matrix
components
normal microbiota - ANSWER symbiotic microbes normally present in and on the
human body, ex bacteria, fungi, few protozoa
why are antibiotics becoming less beneficial? - ANSWER microbes able to pick up DNA
and antibiotic resistance and pass this along to other microbes
when should you take antibiotics? - ANSWER only when absolutely necessary
what 2 things do microbes need for nutrients? - ANSWER carbon and energy
difference between heterotroph and autotrophs - ANSWER where they get their
carbon
heterotroph - ANSWER obtain carbon in an organic form made by other living
organisms such as macromolecules
autotroph - ANSWER organisms that uses inorganic molecules (CO2) as its carbon
source, not nutritionally dependent on other living things
2 classification groups based on how an organism obtains its energy source -
ANSWER chemotroph and phototrophs
chemotroph sub groups - ANSWER chemoorganotrophs and chemolithotrophs
3
UPDATE!!!2025/2026|GUARANTEED PASS|GRADED
symbiotic relationship - ANSWER two organisms live together in a close partnership. at
least one person in the relationship benefits
mutualism - ANSWER obligatory, dependent, both members benefit
commensalism - ANSWER commensal member benefits, the host is not harmed but
does not benefit
parasitism - ANSWER parasite is dependent and benefits, hosts is harmed
3 types of symbiotic relationships - ANSWER mutualism, commensalism, parasitism
non-symbiotic relationship - ANSWER organisms are free living, relationships *not*
required for survival
syntropy - ANSWER communal feeding between organisms in a shared habitat
antagonism/amenalism - ANSWER actions of one organism affect the success of
survival of others in the same community (AKA competition)
2 examples of non-symbiotic relationships - ANSWER syntropy, antagonism/amenalism
1
,action of amenalism - ANSWER can produce toxic substances that inhibit the growth
of other bacteria
how do biofilms communicate? - ANSWER quorum sensing
biofilms - ANSWER result when organisms attach to a substrate by some forming an
extracellular matrix that binds them together in complex organized layers
what dominates the structure of most natural environments on earth? -
ANSWER biofilms
where are biofilms found? - ANSWER both artificial and natural surfaces
biofilm formation steps - ANSWER reversible attachment, irreversible attachment
(quorum sensing), microcolony, mature biofilm, dispersal.
function of matrix - ANSWER allows cells to adhere to each other and to the surface
what happen when a cell loses its flagella? why is this important in biofilm formation? -
ANSWER lose motility and then the biofilm forms. the cells do not need to be mobile,
they are going to stay put in the biofilm, so flagella are not needed
microcolony - ANSWER biofilm beginning to grow in size. first maturation stage
mature biofilm - ANSWER complex biofilm structure, cells diversify, cell growing,
continues to mature
dispersal - ANSWER black and white cells, some with flagella, biofilm can now open
up, free living cells can now leave and form new micro-colonies to make more biolfims
2
, reversible attachment - ANSWER cells attach and detach from the surface
irreversible attachment - ANSWER cells multiply and start producing biofilm matrix
components
normal microbiota - ANSWER symbiotic microbes normally present in and on the
human body, ex bacteria, fungi, few protozoa
why are antibiotics becoming less beneficial? - ANSWER microbes able to pick up DNA
and antibiotic resistance and pass this along to other microbes
when should you take antibiotics? - ANSWER only when absolutely necessary
what 2 things do microbes need for nutrients? - ANSWER carbon and energy
difference between heterotroph and autotrophs - ANSWER where they get their
carbon
heterotroph - ANSWER obtain carbon in an organic form made by other living
organisms such as macromolecules
autotroph - ANSWER organisms that uses inorganic molecules (CO2) as its carbon
source, not nutritionally dependent on other living things
2 classification groups based on how an organism obtains its energy source -
ANSWER chemotroph and phototrophs
chemotroph sub groups - ANSWER chemoorganotrophs and chemolithotrophs
3
