Question

QUESTION 7

Which statement most accurately describes the evolutionaryrelationships among the three domains?

		Bacteria and Archaea diverged from a common ancestor morerecently than they diverged from their common ancestor withEukarya
		Bacteria and Eukarya diverged from a common ancestor morerecently than they diverged from their common ancestor withArchaea
		Eukarya and Archaea diverged from a common ancestor morerecently than they diverged from their common ancestor withBacteria
		All three domains diverged from a common ancestor at the sametime.

10 points

QUESTION 8

Bird influenza is an emerging disease. If you were given thetask of using Koch's postulates of finding the pathogen causingbird flu, what sequence of procedures should you use?

		(1) Inoculate a healthy bird with the suspected pathogen to seewhether it becomes sick, (2) compare symptoms of that bird withthose of a bird known to have the disease, (3) isolate the pathogenfrom both birds in pure culture and stain them to see whether theyare both Gram-positive, and (4) make a vaccine from the pureculture of one bird and inject it into another to see if itrecovers.
		1) Take blood samples from a sick bird, (2) isolate the pathogenin pure culture, (3) treat the bird for the disease and when itrecovers take a second blood sample, and (4) test the blood tocheck whether it no longer contains the pathogen.
		1) Inject a bird with the suspected pathogen, (2) inject anotherbird with a control that doesn't contain the suspected pathogen,(3) repeat with more birds, and (4) plate out samples of blood fromboth kinds of birds to see if you can isolate the pathogen in pureculture.
		(1) Check whether the suspected pathogen is present in sickbirds, then (2) isolate the pathogen from an infected bird and growit in pure culture, (3) inoculate cells from pure culture into ahealthy bird to see whether it causes the disease, and (4) attemptto isolate the suspected pathogen from the inoculated bird.

10 points

QUESTION 9

The evolution of organisms that use oxygen in their respirationwas possible only because of the action of a group of bacteria thatproduced oxygen and changed the Earth's atmosphere from an anoxicone to one rich in oxygen. That group of bacteria was:

		cyanobacteria
		spirochaetes
		proteobacteria
		Staphylococcus

10 points

QUESTION 10

Microcystis aeruginosa is a species of cyanobacteria.What CANNOT be true of this species?

		It synthesizes organic molecules.
		It is an obligate anaerobe
		Its cells contain an extensive thylakoid
		It uses ammonia to produce proteins.