Research the Literature on your Own

• What is the difference between extrinsic and intrinsic noise? Design an experiment that distinguishes between the two.


• Define “epigenetic”. Are stochastic cell fate decisions epigenetic? Why or why not?


• A classic example of a bistable switch is that governing the choice between lysogeny and lytic growth by the bacterial virus lambda. Describe the circuitry governing these alternative states and explain the role of cooperative interactions among phage lambda repressor proteins in the circuit.


• Bacteria spontaneously enter a slow or non-growing “persister” state in which they are resistant to antibiotics. Investigate how this was demonstrated using microfluidics.


• The pathogen Candida albicans switches between two phenotypic states called white and opaque. Is switching genetic or epigenetic and what is the mechanism of switching?


• In the mouse olfactory system, a single odorant receptor gene is expressed in any given neuron to the exclusion of all of other ~2,000 receptor genes. What is the mechanism?

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