Explain why it is unlikely an iron-oxidizing bacterium would thrive in a cold stream with a neutral pH. Also propose an experiment that would test whether iron-oxidizing bacteria are present in the stream
What will be an ideal response?
Answer: In an oxic environment, such as a stream, the iron present in the water will be primarily Fe3+. Iron-oxidizing bacteria require Fe2+ as an electron source, and this form of iron spontaneously oxidizes into Fe3+ by oxygen. Due to such low bioavailability of the necessary Fe2+, it would be unlikely iron-oxidizing bacteria would exist in such a system. Experimental approaches will vary but must make clear measuring loss of Fe2+ supplemented into the stream water is insufficient evidence of microbial transformation. Iron-oxidizing bacteria could be identified in the stream water by classical enrichment approaches and acidifying the stream water to minimize abiotic iron oxidation. Concomitant growth of an isolate with ferric iron precipitation would be strong evidence such bacteria do occur in the stream.
You might also like to view...
The most accurate description of TEMPORAL summation is
A. Several inputs from DIFFERENT presynaptic cells create EPSPs that sum together to bring the neuron over the threshold for an action potential. B. Several inputs from the SAME presynaptic cell arrive in rapid succession, summing into a larger depolarization that brings the neuron over the threshold for an action potential.
Estrogen and progesterone exhibit which type of hormone interaction?
a. synergistic b. permissive c. opposing d. unrelating e. mutual
In the GAL gene system, ________ are cis-acting regulatory elements, and ________ protein is a trans-acting regulatory protein
Fill in the blank(s) with correct word
Biologists currently recognize three kingdoms: Plants, Animals, and Protists.
a. true b. false