¶ … Disease Control. You have been called to a remote area of Uganda to study a mysterious disease that is causing respiratory ailments in a small village. You isolate a bacterium from several patients that seems like a good candidate for the pathogen. How can you determine if this bacterium is causing the illness? I would investigate the bacteria to determine if it had genetic markers consistent with known disease-causing bacteria. I would first prescribe antibiotics to patients and if this cleared up the respiratory ailments then I would assume this bacteria is the cause of the disease.

As a U.S. Department of Agriculture field representative, you counsel a young farmer to plant alfalfa in fields with soils that have low nitrogen levels. You know alfalfa can host certain bacteria.

a. Explain your reasoning.

The growth of alfalfa will ultimately improve the soil, adding much-needed nitrogen and producing a better harvest.

b. How will the alfalfa and its associated bacteria help "fertilize" this farmer's soil?

Bacteria will break down dead matter, and in so doing will add nutrients like nitrogen to the soil.

3. Distinguish between all the following:

a. Obligate anaerobe / obligate aerobe:

Obligate aerobes require oxygen to survive while obligate anaerobes do not an in fact are harmed if exposed to oxygen.

b. Photoautotroph / photoheterotroph:

Photoautotrophs get all the energy they need from light through photosynthesis while photoheterotrophs...

Chemolithotroph / chemoheterotroph:
Chemolithotrophs require minerals to create energy while chemoheterotrophs require oxidation of organic molecules to generate energy.

d. Endotoxin / exotoxin:

Endotoxins are those which are located within the cell wall while exotoxins are released outside of the cell wall.

e. Gram (-) / Gram (+) bacteria:

Gram (+) bacteria have thicker cell walls than Gram (-). Also, Gram (+) bacteria have teichoic acid and more peptidoglycans.

f. Negative single strand RNA virus / positive single stranded RNA virus:

Negative single strand RNA viruses have an antisense strand as opposed to positive single strand RNA viruses which have a sense strand.

4. A friend tells you she "hates" bacteria and declares her intention to eradicate all bacteria from her home using different disinfecting & sterilizing products. How do you respond to her "outrage"? Support your response with 4 specific examples.

I would explain to her that bacteria are necessary for continued life on earth, including human beings. Although there are negative bacteria which can cause harm, there are many bacteria which are beneficial to humans. These include: lactobacillus acidophilus which is yogurt, yeast which makes bread and cake, coliform bacteria in the intestines which helps break down food, streptomyces are used to make antibiotics, and rhizobium which breaks down matter to put nutrients into…