A follicle is a small, spherical or vase-like group of cells enclosing a cavity in which some other structure grows or other material is contained. Thyroid follicles make up the

thyroid gland The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The thy ...

. Follicles are best known as the sockets from which hairs grow in humans and other

mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fu ...

s, but the bristles of

annelid The annelids (Annelida , from Latin ', "little ring"), also known as the segmented worms, are a large phylum, with over 22,000 extant species including ragworms, earthworms, and leeches. The species exist in and have adapted to various ecolo ...

worms also grow from such sockets.

References

{{reflist Skin anatomy Cells