What is Notopodium in zoology?
Noun. notopodium (plural notopodia) (zoology) The dorsal lobe or branch of a parapodium.
Where is parapodium found?
Parapodia are predominantly found in annelids, where they are paired, un-jointed lateral outgrowths that bear the chaetae. In several groups of sea snails and sea slugs, ‘parapodium’ refers to lateral fleshy protrusions.
What animals have chaetae?
A chaeta or cheta (from Greek χαίτη “crest, mane, flowing hair”; plural: chaetae) is a chitinous bristle or seta found in annelid worms, (although the term is also frequently used to describe similar structures in other invertebrates such as arthropods).
What do chaetae do?
Chaetae are involved in the locomotion of the worm and this can be illustrated by allowing a worm to move over a piece of rough paper and then a sheet of glass. With this hold the contraction of longitudinal muscles, within the body wall, draws the body forward, the chaetae on the moving portion being withdrawn.
What is Prostomium in zoology?
The prostomium (From Ancient Greek, meaning “before the mouth”; plural: prostomia; sometimes also called the “acron”) is the cephalized first body segment in an annelid worm’s body at the anterior end. The prostomium together with the peristomium, which includes the mouth and pharynx, make up the annelid head.
What is Notopodium and neuro podium?
In zoology, a neuropodium, or neuropodia in plural form, pertains to the ventral lobe of the parapodium of the polychaetes. The notopodium is the dorsal lobe whereas the neuropodium is the ventral lobe of the parapodium.
Is Earthworm a parapodia?
The basic features of locomotion in annelids are most easily observed in the earthworm because it lacks appendages and parapodia.
What is the meaning of parapodia in English?
1 : either of a pair of fleshy lateral processes borne by most segments of a polychaete worm. 2 : a lateral expansion on each side of the foot usually forming a broad swimming organ in some gastropods.
How are chaetae arranged?
The chaetae are usually arranged in four discrete bundles per segment (two ventro-lateral and two dorso-lateral). Other chaetae (usually called crotchets) are normally shorter and broader, usually sigmoid in shape with a swelling (nodulus) along their shaft and often have a bifid (forked) or …
What is the difference between chaetae and setae?
The key difference between setae and chaetae is that setae are bristle-like structures present in both vertebrates and invertebrates, while chaetae are chitinous bristle-like structures present in most fungal species.
What is segmentation in zoology?
Segmentation, also called metamerism, or metameric segmentation, in zoology, the condition of being constructed of a linear series of repeating parts, each being a metamere (body segment, or somite) and each being formed in sequence in the embryo, from anterior to posterior.
Which is the best definition of notopodium?
Definition of notopodium. : the dorsal lobe or branch of a parapodium.
What kind of Cirrus does a notopodium have?
Single dorsal cirrus on each notopodium. Two types of notose- tae: 1) white and thin capillary setae, with an elongated tip and serrated margin, and 2) hook-shaped uncini, straight, and margin with 9 to 11 rows of spines (Fig Id).
Where did the parapodium get its name from?
Parapodium is from Lepidonotus oculatus and is a Museums Victoria specimen. Microscope photograph of a parapodium from a specimen of Arctonoe sp. showing the internal acicula that support the two lobes of the parapodium. This parapodium is from a Museums Victoria specimen.
How many thoracic segments are there in the notopodium?
There are 8 thoracic segments and paleae are present in the inferior thoracic notopodium. Abdominal capillary neurosetae are in a line, paleae are absent, and the manubrum is short in notopodial tori. Single dorsal cirrus on each notopodium.