1) Think about how antibiotic resistance to Rifampin (an antibiotic used to treat TB) evolves. Then, put the following steps in order; note that not all of the steps may be involved in the process.
1 = lung cells are colonized by bacteria that cause tuberculosis; one bacterial cell has a mutated version of the gene that codes for RNA polymerase
2 = the human lung cells are no longer able to properly transcribe DNA, and begin to die off; if left untreated, this disease may become fatal.
3 = antibiotic treatment using Rifampin begins
4 = bacteria that are resistant to Rifampin proliferate, and the mutated RNA polymerase gene becomes common in the bacterial population; the human patient's health deteriorates
5 = the bacterial cells divide by binary fission and the patient is diagnosed with TB
6 = bacteria that are susceptible to Rifampin die because these cells cannot carry out transcription
2) Which of the following is LEAST likely to influence the pattern of succession in a recently disturbed terrestrial habitat?
a) the amount of available sunlight
b) existing species in the habitat
c) soil nutrient levels
d) the amount of CO2
e) the amount of open space
3) An abundance of nitrogen (N) and phosphorus (P) in an aquatic environment will eventually lead to __________ levels of dissolved oxygen due to __________.
a. high; high rates of photosynthesis by producer populations
b. high; the abundance of anaerobic bacteria
c. low; high rates of cellular respiration by decomposer populations
d. low; high rates of photosynthesis by producer populations