Which of the following is NOT a toxic substance found in tobacco? 1. tar
2. carbon monoxide
3. cocaine
4. nicotine
Im confused. Arent they all harmful?

Hand washing is an important behavior that can cut down your chances of becoming sick with a communicable disease. select the best answer from the choices provided. t f

Which of the following best reflects what we know about how the flu virus moves between species? a) the flu virus in a pig is mutated and replicated in alternate arrangements so that humans who eat the pig products can be infected. b) a flu virus from a human epidemic or pandemic infects birds; the birds replicate the virus differently and then pass it back to humans. c) an influenza virus gains new sequences of dna from another virus, such as a herpesvirus; this enables it to be transmitted to a human host. d) an animal such as a pig is infected with more than one virus, genetic recombination occurs, the new virus mutates, the virus is passed to a new species such as a bird, and the virus mutates again and can now be transmitted to humans.

Aproper cool-down routine includes which of the following? a). eating a good-sized meal b. five to 10 minutes of slow walking or jogging and stretching c). less than 5 minutes of cool-down stretches d). sprinting or other strenuous exercise