Category: S

A muscle that encircles a duct, tube, or opening in such a way that contraction constricts the opening. A muscle that encircles a duct, tube, or orifice, thus controlling its opening.  

A ringlike muscle that controls a natural orifice. A circular band of muscle which surrounds an opening or passage in the body, especially the anus, and can narrow or close the opening or passage by contracting. A muscle, surrounding a body opening or vessel, that can contract and close that opening. Circular band of muscle…

Wedge shaped. Relating to the sphenoid bone. Shaped like a wedge. A bone lying in the centre of the base of the skull, and supporting the others like a wedge or keystone. Having the form of a wedge. The bone with a wedge-like shape situated at the base of the skull.  

The ability of a sperm cell to swim quickly toward the ovum and fertilize it.  

A method of gender selection in which X-bearing and Y-bearing sperm are separated and the woman is artificially inseminated with the desired sperm.  

A spermicide in suppository form that effervesces or dissolves when it comes in contact with the moisture and warmth of the vagina.  

A chemical used to kill sperm.  

The tube in males that conveys the sperm from the epididymis to the seminal vesicles and urethra.  

A center where a man’s semen may be frozen and stored for later use in artificial insemination. A place where sperm can be stored for use in artificial insemination. A privately run organization that collects sperm from donors, sometimes paying a fee, and sells it to women or doctors for use in artificial insemination. Such…

Primitive male germ cells that mature into primary spermatocytes.