1 Sulfur Crystals: History and its Uses Sulfur is a chemical element that is widely abundant in nature. 2  It is classified as a multivalent non-metal. 3  Sulfur's symbol is S and its atomic number 16.
Question and answer. The __________ and __________ are the glands that stimulate reproductive cycles. A. testes. . . thyroid B. testes. . . ovaries C. ovaries. . . thyroid D. ovaries. . . thymus. The testes and ovaries are the glands that stimulate reproductive cycles. Expert answered| emdjay23 |Points 2484|.
The testes and ovaries, or gonads, are perhaps the most familiar endocrine glands. In males, testes produce sperm and secrete the male sex hormone testosterone; in females, ovaries produce eggs and the female hormone estrogen.