Where would a disease transmitted by person-to-person contact be most likely to spread quickly?

The structure that houses the cells genetic information.

Explain the process that creates the heat of the sun?

Abird flies by moving its wings up and down. which two systems are most directly responsible for the movement of a bird's wings? a. skeletal and muscular systems b. respiratory and muscular systems c. skeletal and digestive systems d. respiratory and digestive systems