Questions and CORRECT Answers
What happened to the E coli in the petri dish?
A. The e. coli developed a new gene
B. The E. coli intentionally changed the sequence of one of its genes to avoid the antibiotic
C. A random DNA mutation occurred that altered the function or expression of an existing
enzyme
D. The E. coli turned on a different metabolic pathway to avoid the antibiotic. - CORRECT
ANSWER -C
If the experiment had been performed with a diverse group of bacteria, some of which had some
resistance to trimethoprim, how might the results have been different?
A. The results would have been the same.
B. The bacteria with pre-existing resistance would have dominated.
C. It depends on how quickly e. coli could alter their genome to adapt to the antibiotic. -
CORRECT ANSWER -B
What should a graph of Frequency vs. complexity of organisms look like - CORRECT
ANSWER - Right skewed... as time progresses, we get more complex organisms, and old
ones remain... this is due to mutations...mode on X axis doesnt change!
optic density - CORRECT ANSWER - How much light is scattered - the more light the
more bacteria in the solution
Why are there still bacteria?
A. Because disease causing organisms serve a role in nature
B. They are necessary for the eukaryotes to survive
C. Nothing has out-competed them where they live
D. They're really tiny so nothing can eat them.
, E. Simplicity never goes out of style. - CORRECT ANSWER -C
When looking at a graph of Expansion during evolution of the Cit+ phenotype; comparing
generation of E.coli and OD, what does the OD tell us abt the E.coli?
A. How many bacteria there are in solution.
B. How many generations of e. coli have elapsed
C. The ability of e. coli to use citrate
D. Whether the e. coli are myopic. - CORRECT ANSWER -C
After 33,000 generations... - CORRECT ANSWER - The cells go through more divisions
in 24 hours and they are able to make use of citrate
an adaptation - CORRECT ANSWER - - A trait that allows some individuals to survive in
certain environments relative to individuals without that trait.
- They Evolve by genetic change that occurs over generations in response to natural selection in
a population
Acclimation - CORRECT ANSWER - Involves physiological changes in an individual to
thrive in an environment
Natural selection - CORRECT ANSWER - Gradual non-random process by which traits
become more or less common in a species based on DIFFERENTIAL REPRODUCTION
artifical selection - CORRECT ANSWER - Non-random process by which traits become
more or less common in a species because humans are selecting which organisms have offspring
Evolution - CORRECT ANSWER - Through tine, species accumulate differences; as a
result descendants differ from their ancestors. In this way, new species arise from existing ones.
These differences are PHENOTYPIC but "based" in the genome