What is annulus?

What is annulus?

Definition of annulus 1 : ring. 2 : a part, structure, or marking resembling a ring: such as. a : a line of cells around a fern sporangium that ruptures the sporangium by contracting. b : a growth ring (as on the scale of a fish) that is used in estimating age.

What is annular zone?

Noun. annular zone (plural annular zones) (mycology) A ring of fibers on the stem of a mushroom that is not well enough defined to be called an annulus.

How many sides does a annulus have?

An annulus is a flat shape like a ring. Its edges are two circles that have the same center. Something shaped like an annulus is said to be annular.

What is annuli earthworm?

Earthworms' bodies are made up of ringlike segments called annuli. These segments are covered in setae, or small bristles, which the worm uses to move and burrow. ... As they burrow, they consume soil, extracting nutrients from decomposing organic matter like leaves and roots.

What is an annulus on a door?

A ring; the ring of a door.

What is annulus in heart?

The mitral annulus constitutes the anatomical junction between the ventricle and the left atrium, and serves an insertion site for the leaflet tissue. It is often divided segmentally according to the site of leaflet insertion (the anterior or posterior annulus).

What is annulus in oil and gas?

The annulus of an oil well or water well is any void between any piping, tubing or casing and the piping, tubing, or casing immediately surrounding it. ... The 'A' annulus can serve a number of crucial tasks, including gas lift and well kills.

What shape is an annulus?

In mathematics, an annulus (plural annuli or annuluses) is the region between two concentric circles. Informally, it is shaped like a ring or a hardware washer. The word "annulus" is borrowed from the Latin word anulus or annulus meaning 'little ring'. The adjectival form is annular (as in annular eclipse).

What do you call a 3d annulus?

Coaxial or annular cylinder. In a sphere it's a spherical ring.

What is annuli and Septa?

Earthworms belong to the phylum annelida which comprises segmented worms. The segments of the earthworm's body, known as annuli, are separated by transverse dividing walls known a septa.

What is an open annulus?

• In mathematics, an annulus (the Latin word for "little ring" is anulus / annulus, with plural anuli / annuli) is a ring-shaped object, a region bounded by two concentric circles. The adjectival form is annular (as in annular eclipse ). The open annulus is topologically equivalent to both...

What is the meaning of anulus?

• Define anulus. anulus synonyms, anulus pronunciation, anulus translation, English dictionary definition of anulus. n. 1. A circular object, form, line, or arrangement. 2. A small circular band, generally made of precious metal and often set with jewels, worn on the...

What is the punctured disk of an annulus?

• If r is 0, the region is known as the punctured disk (a disk with a point hole in the center) of radius R around the point a . As a subset of the complex plane, an annulus can be considered as a Riemann surface. The complex structure of an annulus depends only on the ratio r

What is an annulus in a Crab Tree?

• An annulus, or dark ring, is formed each winter between the cementum formed in spring and summer growth periods. — Alan Clemons, Outdoor Life, They are easily identified by the red-brown cap fading to tan, white to lilac-gray gills, firm texture, and annulus (ring) around the stout stipe (stalk).