BIS 2C Final Exam
Major differences between Prokaryotes and Eukaryotes - ANS Prokaryotic: Lack membrane bound
organelles, lack a nuclues, divide by binary fission not mitosis, have peptidoglycan in cell wall
Eukaryotes: Have membrane bound organelles, have a membrane enclosed nucleus, divide by
mitosis, do not have peptidoglycan in cell wall
Lateral Gene Transfer - ANS The transfer of genetic material to unrelated organisms.
Transformation,Conjugation, and Transduction
Similarities of LGT and Sexual Reproduction - ANS Transfer of genetic information, variety of genes,
selection takes place, requires two organisms, recombination occurs, both create new genetic
combinations
Differences between LGT and Sexual Reproduction - ANS Sexual: Two identical organisms, one way to
be done, entire genome is transferred
LGT: Can occur between two different species or domains, donor-receptor relationship, doesn't
transfer the full genome, there are many different ways to do LGT
What is the relationship of LGT to phylogeny reconstruction? - ANS It complicates phylogenetic
analysis because many different genes can be passed between different species. Makes it hard to tell
what is convergent evolution, derived, ancestral, or if it was LGT
How is LGT different from convergent evolution? - ANS Convergent evolution is when two distantly
related groups evolve the same adaptation independently; LGT is different because the adaptation is
physically transferred between the two groups.
What is quorum sensing? - ANS Bacteria "talk" to each other
Bacteria are "multi-cellular"
Bacteria can distinguish self from other
Discovered by Bonnie Bassler and team
Bacteria send out signal and other bacteria can understand them and identify them
What are the main steps in quorum sensing? - ANS 1) Signal producing proteins are produced and
released from the bacteria
,2) Signal proteins attach to signal receptors on each individual bacteria and they can identify if the
receptor is from their own species or from another species
Why is quorum sensing important? - ANS It's important because it explains how bacteria know when
to start attacking a host (send a chemical signal to say they have enough bacteria to take over) and
they can identify each other and other bacteria in their midst. Allows for communication between
bacteria
What is a biofilm? - ANS Extracellular polysaccharide matrix
Surface attachment
Solid surfaces
Soft tissue in living organisms
Liquid-air interface
Structural heterogeneity
Genetic diversity- bacteria, archaea, protists, fungi, algae
Embedded in the extracellular matrix; can attach to a variety of things; not uniform (structural
heterogeneity)
Biofilm steps - ANS Attachment and aggregation (free-swimming prokaryotes bind to a surface, grow
and divide) => extracellular matrix production => behavior and communication (signal molecules to
attract same species) => generation of heterogeneity (signal molecules to attract different species)
What is a virus (1)? - ANS A non-cellular infectious agent that can replicate only inside the living cells
of organisms using the existing cellular machinery and cause the synthesis of specialized elements
(virions, virus particles) which can transfer the infection to new cells.
What are the main components of a virus? - ANS Nucleic acid, capsid (protein coat), envelope (lipid
membrane=not all)
What is a virus (2)? - ANS Intracellular parasites with nucleic acids that are capable of directing their
own replication and are not cells
What three things must viruses be able to do if they are to survive in the real world? - ANS 1) Get
into the susceptible host 2) Replicate and make more virus 3) Have some mechanism to move the
newly made virus to new susceptible hosts
, Basic virus "life cycle" - ANS Attachment to host cell membrane, penetration of host cell membrane,
uncoating, replication, self-assembly of virus particles, and release from the cell
How does a virus penetrate a host's cell membrane? - ANS Endocytosis (tricking the cell), mechanical
penetration (trauma, vector), or they inject their genome with some bacterial viruses (insects?)
Symbiosis - ANS The living together of two or more species in a prolonged and intimate relationship
Types of symbiosis - ANS Mutualism, commensalism, parasitism
Mutualism - ANS A type of interaction between species that benefits both species (Ex: Rhizobium and
plants)
Commensalism - ANS A type of interaction in which species in which one participant benefits while
the other is unaffected (Ex: clown fish and sea anemones)
Parasitism - ANS A relationship where one species benefits at the expense of the other (ex:
Mosquitos and humans)
Importance of the human microbiome - ANS 90% of the cells in the human body are microbial cells;
skin, conjunctiva, oral cavity, intestinal tract, upper respiratory tract, urogenital tract; each person
has a different finger tip microbial community; Amniotic fluid bacteria, breast milk, external breast
microbes, uterus, and vagina are all important for helping a baby develop an immune system when it
is first born; helps with digestion and many other body functions
Key points about the human microbiome - ANS There is quite a bit of variation from person to
person, but one's own microbiome is fairly stable over time; The microbiomes of various body sites
are similar to everyone (thus your skin microbiome is more similar to other people's skin
microbiomes than to your gut microbiome); When microbiomes are classified by the bacterial
species they contain, they look very different from person to person; If microbiomes are classified by
the presence of various functional capabilities, they look more similar from person to person
Functional capabilities of the human microbiome - ANS The ability to digest different kinds of carbs,
synthesize vitamins, break down toxins, etc
Current research directions on microbial communities on hum ANS - ANS Studies in obesity, autism,
Crohn's diesease
Major differences between Prokaryotes and Eukaryotes - ANS Prokaryotic: Lack membrane bound
organelles, lack a nuclues, divide by binary fission not mitosis, have peptidoglycan in cell wall
Eukaryotes: Have membrane bound organelles, have a membrane enclosed nucleus, divide by
mitosis, do not have peptidoglycan in cell wall
Lateral Gene Transfer - ANS The transfer of genetic material to unrelated organisms.
Transformation,Conjugation, and Transduction
Similarities of LGT and Sexual Reproduction - ANS Transfer of genetic information, variety of genes,
selection takes place, requires two organisms, recombination occurs, both create new genetic
combinations
Differences between LGT and Sexual Reproduction - ANS Sexual: Two identical organisms, one way to
be done, entire genome is transferred
LGT: Can occur between two different species or domains, donor-receptor relationship, doesn't
transfer the full genome, there are many different ways to do LGT
What is the relationship of LGT to phylogeny reconstruction? - ANS It complicates phylogenetic
analysis because many different genes can be passed between different species. Makes it hard to tell
what is convergent evolution, derived, ancestral, or if it was LGT
How is LGT different from convergent evolution? - ANS Convergent evolution is when two distantly
related groups evolve the same adaptation independently; LGT is different because the adaptation is
physically transferred between the two groups.
What is quorum sensing? - ANS Bacteria "talk" to each other
Bacteria are "multi-cellular"
Bacteria can distinguish self from other
Discovered by Bonnie Bassler and team
Bacteria send out signal and other bacteria can understand them and identify them
What are the main steps in quorum sensing? - ANS 1) Signal producing proteins are produced and
released from the bacteria
,2) Signal proteins attach to signal receptors on each individual bacteria and they can identify if the
receptor is from their own species or from another species
Why is quorum sensing important? - ANS It's important because it explains how bacteria know when
to start attacking a host (send a chemical signal to say they have enough bacteria to take over) and
they can identify each other and other bacteria in their midst. Allows for communication between
bacteria
What is a biofilm? - ANS Extracellular polysaccharide matrix
Surface attachment
Solid surfaces
Soft tissue in living organisms
Liquid-air interface
Structural heterogeneity
Genetic diversity- bacteria, archaea, protists, fungi, algae
Embedded in the extracellular matrix; can attach to a variety of things; not uniform (structural
heterogeneity)
Biofilm steps - ANS Attachment and aggregation (free-swimming prokaryotes bind to a surface, grow
and divide) => extracellular matrix production => behavior and communication (signal molecules to
attract same species) => generation of heterogeneity (signal molecules to attract different species)
What is a virus (1)? - ANS A non-cellular infectious agent that can replicate only inside the living cells
of organisms using the existing cellular machinery and cause the synthesis of specialized elements
(virions, virus particles) which can transfer the infection to new cells.
What are the main components of a virus? - ANS Nucleic acid, capsid (protein coat), envelope (lipid
membrane=not all)
What is a virus (2)? - ANS Intracellular parasites with nucleic acids that are capable of directing their
own replication and are not cells
What three things must viruses be able to do if they are to survive in the real world? - ANS 1) Get
into the susceptible host 2) Replicate and make more virus 3) Have some mechanism to move the
newly made virus to new susceptible hosts
, Basic virus "life cycle" - ANS Attachment to host cell membrane, penetration of host cell membrane,
uncoating, replication, self-assembly of virus particles, and release from the cell
How does a virus penetrate a host's cell membrane? - ANS Endocytosis (tricking the cell), mechanical
penetration (trauma, vector), or they inject their genome with some bacterial viruses (insects?)
Symbiosis - ANS The living together of two or more species in a prolonged and intimate relationship
Types of symbiosis - ANS Mutualism, commensalism, parasitism
Mutualism - ANS A type of interaction between species that benefits both species (Ex: Rhizobium and
plants)
Commensalism - ANS A type of interaction in which species in which one participant benefits while
the other is unaffected (Ex: clown fish and sea anemones)
Parasitism - ANS A relationship where one species benefits at the expense of the other (ex:
Mosquitos and humans)
Importance of the human microbiome - ANS 90% of the cells in the human body are microbial cells;
skin, conjunctiva, oral cavity, intestinal tract, upper respiratory tract, urogenital tract; each person
has a different finger tip microbial community; Amniotic fluid bacteria, breast milk, external breast
microbes, uterus, and vagina are all important for helping a baby develop an immune system when it
is first born; helps with digestion and many other body functions
Key points about the human microbiome - ANS There is quite a bit of variation from person to
person, but one's own microbiome is fairly stable over time; The microbiomes of various body sites
are similar to everyone (thus your skin microbiome is more similar to other people's skin
microbiomes than to your gut microbiome); When microbiomes are classified by the bacterial
species they contain, they look very different from person to person; If microbiomes are classified by
the presence of various functional capabilities, they look more similar from person to person
Functional capabilities of the human microbiome - ANS The ability to digest different kinds of carbs,
synthesize vitamins, break down toxins, etc
Current research directions on microbial communities on hum ANS - ANS Studies in obesity, autism,
Crohn's diesease
