Question

Phototrophs need an electron source like H₂S orH₂O. Where do the electrons from these sources go?(Assume the organism is growing autotrophically as well astophototrophically.)

	O2 and CO2
	O2 only
	CO2 only
	Sulfate or oxygen
	Inorganic various molecules, depending on cellular needs.

2.

Which of the following statements about chlorophyll istrue?

	It is a good electron acceptor in its oxidized form.
	It is a good electron donor in its reduced form when energizedby light.
	It contains magnesium.
	It is a tetrapyrrole.
	All of the above

3.

The unifying feature of all photosynthetic organisms isa(n)

	electron transfer chain.
	electron donating system to generate NADPH.
	ATP-generating system.
	light-gathering system.
	All of the above

4.

Evidence suggests that banded iron formations are due to

	chemical oxidation of reduced iron, Fe2+.
	aerobic reduction of insoluble ferric iron, Fe(OH)3.
	anaerobic oxidation of soluble ferrous iron,Fe2+.
	Both a and b
	Both a and c

5.

In addition to their ability to harvest light in the 400 to 500nm range, carotenoids also

	eject electrons from the reaction center.
	function as a tetrapyrrole.
	intercept toxic single-state oxygen.
	transfer electrons to ubiquinone.
	raise electrons to a higher energy state.

6.

Ribosomal RNA and other cell features affirm that living cellsshould be divided into three groups called domains.

	True
	False

7.

Microbes have started to evolve recently.

	True
	False

8.

The ________ was essential for the evolution of oxygenicphotosynthesis.

	evolution of cyanobacteria
	development of photosystem I
	ability to extract electrons from CO2
	ability to extract electrons from H2O
	ability to use oxygen as the terminal electron acceptor

9.

What do oxygenic phototrophs use as an electron source?

	Oxygen
	Sulfide
	Water
	Organic compounds
	CO2

10.

Three domains of organisms have been established basedprimarily on size and other structural features of the cells.

	True
	False