CK-12 Foundation
Ck 12: Biology: Human Sperm
[Free Registration/Login may be required to access all resource tools.] Discusses how sperm are produced.
CK-12 Foundation
Ck 12: Life Science: Human Sperm
[Free Registration/Login may be required to access all resource tools.] Sperm, the male reproductive cells, are tiny. In fact, they are the smallest cells in the human body. Some people think that they look like tadpoles. Learn more...