Khan Academy
Khan Academy: Psychoactive Drugs: Depressants and Opiates
An explanation of the effects the psychoactive drugs, depressants and opiates, have on the body.
CK-12 Foundation
Ck 12: Biology: Control of Viruses
[Free Registration/Login may be required to access all resource tools.] Describes how viruses can be controlled by vaccines and antiviral drugs.