1.  During the carboxylation phase of the Calvin cycle, CO2 combines with
A.ribulose 1,5 - bisphosphate
B.phosphoglyceraldehyde
C.pyruvic acid
D.oxaloacetic acid

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2.  Which of the following groups contain(s) many unique coenzymes, such as coenzyme M and coenzyme F420?
A.Sulfate-reducing bacteria
B.Methanotrophs (methane-oxidizing microbes)
C.Methanogens (methane-producing microbes)
D.Acetogens (acetigens; acetate-producing microbes)

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3. In the passive diffusion, solute molecules cross the membrane as a result of
A.concentration difference
B.pressure difference
C.ionic difference
D.all of these

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4. In an oxygenic photosynthesis, the green and the purple bacteria do not use which of the following one as an electron source?
A.H2O
B.H2
C.H2S
D.S (elemental sulphur)

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5. Radioisotopes are frequently used in the study of cells. Assume a culture of E. coli is grown in a culture medium containing radioactive phosphorous. At the end of 48 hours, it is expected to find the radioactive label located in
A.enzymes
B.RNA
C.phospholipids
D.all of these

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6. Assimilatory sulfate reduction involves the nucleotide __________ during the incorporation of H2S in the production of __________ .
A.ATP; methionine
B.ATP; cytosine
C.UTP; cytosine
D.GTP; cytosine

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7. The chlorophyll molecules used by eucaryotes and cyanobacteria absorb radiant energy in the____________portion(s) of the visible spectrum.
A.red
B.green
C.red and blue
D.green and ultraviolet

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