Descending facilitation from the brainstem enhances chronic pain signals.

BDNF-induced KCC2 downregulation reverses GABA-mediated inhibition to excitation.

Astrocytes are activated earlier than microglia after nerve injury.

Why is the sign of cross-price elasticity often more relevant than the magnitude? Explain and provide two examples.

Identify the conditions for perfect competition:

Identify the demand shifters for a good:

Identify the conditions for a monopoly:

Many environmentalists are horrified by the notion of marketable pollution permits advocated by economists. These environmentalists insist that pollution is wrong, and that no one should be able to buy the right to pollute the environment. What do you think? Can moral suasion be used instead? Explain.  

Which enzyme unwinds the DNA helix during replication?

Hepatitis B virus is transmitted by: OA.    the respiratory route OB.    vectors OC.    fomites OD.    fecal/oral route XE.    several routes (e.g. in blood products, IV drug use, sexually, etc)