Yellow fever, encephalitis, and measles are diseases in humans. The disease-causing agents take over the machinery
of the cells and use it to reproduce.
Based on this information, the agents that cause these
diseases are which of the following?

hormones in blood stream

image: dtc.ucsf.edu

endocrine glands secrete hormones into the blood stream near them; the hormones then travel in our bloodstream until it reaches its destination, called a target cell, in distance parts of the body. in the target tissue, hormones lock onto the target’s plasma membrane, called the receptor site.