BIOLOGY 251 EXAM 2 QUESTIONS WITH COMPLETE
AND ONLY CORRECT ANSWERS (SORRENTINO -
EUKARYOTES LECTURE)
microorganisms that may be present for days, weeks, or months. - answer ✔✔-What are transient
microbiota?
microorganisms that permanently colonize the host. - answer ✔✔-What are resident microbiota?
symbiotic organisms, one of which benefits from the relationship ,and the other of which neither gains
nor loses from the relationship.
example: tarantula and frog in the rainforest - answer ✔✔-What are commensals?
symbiotic organisms that benefit from slowly taking organic material and energy from other organisms
("hosts")
example: the sea lamprey sucking fish. - answer ✔✔-What are parasites?
They do NOT kill their hosts. - answer ✔✔-What do the most efficient parasites do?
Yes. An example is the relationship between people and E. Coli.
However, E. Coli are INSIDE the body of a human but OUTSIDE of human cells. - answer ✔✔-Can
unicellular organisms and multicellular organisms be in symbiosis?
Yes, they can.
An example is the relationship between a sea squirt and cyanobacterium.
Sea squirts get energy in glucose and cyanobacterium gets protection.
This pair is an example of mutualistic intracellular symbiotes. - answer ✔✔-Can symbiotic unicellular
organisms exist inside other cells?
Evidence strongly indicates that the first eukaryotic cells resulted from a permanent association of an
archaeal cell and its intracellula rbacterial symbiotes. - answer ✔✔-Why is the idea of an intracellular
symbiote important to us?
About 3.8 billion years ago: ancient bacteria became intracellular symbiotes inside ancient archaea;
symbiosis became permanent. This lead to the conclusion that descendants of these bacteria are
modern mitochondria.
About 2.8 billion years ago, ancient cyanobacteria became intracellular symbiotes inside ancient
eukaryotic cells; symbiosis became permanent. This lead to the conclusion that descendants of these
cyanobacteria are modern chloroplasts - answer ✔✔-How do we think that eukaryotic cells first came
to be?
one (1) ancestral population and ALL of its descendants - answer ✔✔-What is a monophyletic group?
multiple populations, but with no necessarily predictable relationship among them - answer ✔✔-What
is a polyphyletic group?
one (1) ancestral population and SOME of its descendants - answer ✔✔-paraphyletic group
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AND ONLY CORRECT ANSWERS (SORRENTINO -
EUKARYOTES LECTURE)
microorganisms that may be present for days, weeks, or months. - answer ✔✔-What are transient
microbiota?
microorganisms that permanently colonize the host. - answer ✔✔-What are resident microbiota?
symbiotic organisms, one of which benefits from the relationship ,and the other of which neither gains
nor loses from the relationship.
example: tarantula and frog in the rainforest - answer ✔✔-What are commensals?
symbiotic organisms that benefit from slowly taking organic material and energy from other organisms
("hosts")
example: the sea lamprey sucking fish. - answer ✔✔-What are parasites?
They do NOT kill their hosts. - answer ✔✔-What do the most efficient parasites do?
Yes. An example is the relationship between people and E. Coli.
However, E. Coli are INSIDE the body of a human but OUTSIDE of human cells. - answer ✔✔-Can
unicellular organisms and multicellular organisms be in symbiosis?
Yes, they can.
An example is the relationship between a sea squirt and cyanobacterium.
Sea squirts get energy in glucose and cyanobacterium gets protection.
This pair is an example of mutualistic intracellular symbiotes. - answer ✔✔-Can symbiotic unicellular
organisms exist inside other cells?
Evidence strongly indicates that the first eukaryotic cells resulted from a permanent association of an
archaeal cell and its intracellula rbacterial symbiotes. - answer ✔✔-Why is the idea of an intracellular
symbiote important to us?
About 3.8 billion years ago: ancient bacteria became intracellular symbiotes inside ancient archaea;
symbiosis became permanent. This lead to the conclusion that descendants of these bacteria are
modern mitochondria.
About 2.8 billion years ago, ancient cyanobacteria became intracellular symbiotes inside ancient
eukaryotic cells; symbiosis became permanent. This lead to the conclusion that descendants of these
cyanobacteria are modern chloroplasts - answer ✔✔-How do we think that eukaryotic cells first came
to be?
one (1) ancestral population and ALL of its descendants - answer ✔✔-What is a monophyletic group?
multiple populations, but with no necessarily predictable relationship among them - answer ✔✔-What
is a polyphyletic group?
one (1) ancestral population and SOME of its descendants - answer ✔✔-paraphyletic group
GRADESMORE.COM
