Body orifice

A body orifice is any opening in the body of an animal.

External

In a typical mammalian body such as the human body, the external body orifices are:

• The nostrils, for breathing and the associated sense of smell
• The mouth, for eating, breathing, and vocalizations such as speech
• The ear canals, for the sense of hearing
• The nasolacrimal ducts, to carry tears from the lacrimal sac into the nasal cavity
• The anus, for defecation
• The urinary meatus, for urination and ejaculation
• In females, the vagina, for menstruation, sexual intercourse and childbirth
• The nipple orifices

Other animals may have some other body orifices:

• cloaca, in birds, reptiles, amphibians, and some other animals
• siphon in mollusk, arthropods, and some other animals

Internal

Internal orifices include the orifices of the outflow tracts of the heart, between the heart valves.

See also

• Mucosa
• Mucocutaneous boundary
• Meatus
• Body cavity