muscular ring that controls flow in and out of an organ

any of the pairs of nerves that arise from the spinal cord

Repair by regeneration is sometimes possible.

the presence of excess fat in faeces

bile pigment found in faeces and responsible for the characteristic colour of faeces

the destruction of all microorganisms and their spores

muscle fibres that have striations and are under voluntary control; also called skeletal muscle

under the skin

the deepest layer of skin composed mainly of adipose tissue

gland in the dermis of the skin that secretes sweat