[Solved] When a malfunctioning kidney is replaced with a donor kidney, it is called a kidney or ________. (two words) Estrogen: A group of sex hormones crucial for the development and functioning of female reproductive tissues, and also involved in various other body processes. Testosterone: A steroid hormone that is the primary male sex hormone, responsible for the development of male secondary sexual characteristics. Pornography: Material designed to stimulate sexual excitement through the depiction of sexual activities or content. Initiate Sex: The act of starting sexual activity or making moves that suggest the desire for sexual engagement.