Proteins from outside a cell that stimulate it to divide are called a. oncogenes. b. stem cells. c. cyclins. d. growth factors

That would be, D. Growth factors

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.