noun
definition
A feeding organ of brachiopods, bryozoans and phoronids.
Examples of lophophore in a Sentence
Its two lips fusing together at the corners of the mouth are prolonged into the socalled arms. These arms, which together form the lophophore, TV.
The great arm-sinus of each side of the lophophore lies beneath the fold or lip which together with the tentacles forms the ciliated groove in which the mouth opens.
The small arm-sinus runs along the arms of the lophophore at the base of the tentacles, and gives off a blind diverticulum into each of these.
It is a remarkable fact that in Discinisca, although the vessels to the lophophore are arranged as in other Brachiopods, no trace of a heart or of the posterior vessels has as yet been discovered.
The lophophore and stalk are largely composed of this tissue.
Like the chief armnerve, this strand runs through the lophophore, parallel indeed with the former except near the middle line, where it passes ventrally to the oesophagus.
The lophophore is supplied by yet a third nerve, the under arm-nerve, which is less clearly defined than the others, and resembles a moderate aggregation of the nerve fibrils, which seem everywhere to underlie the ectoderm, and which in a few cases are gathered up into nerves.
The chaetae drop off, and the lophophore is believed to arise from thickenings which appear in the dorsal mantle lobe.
By this time the eyes have disappeared, the four bundles of chaetae have dropped off, and the lophophore has begun to appear as an outgrowth of the dorsal mantle lobe.
The polypide consists of a "lophophore" bearing a series of ciliated tentacles by which Diatoms and other microscopic bodies are collected as food, of a U-shaped alimentary canal, and of a central nervous system.
The lophophore is a simple circle in all Polyzoa except in the Phylactolaemata, where it typically has the form of a horse shoe outlined by the bases of the tentacles.
The cavities of the hollow tentacles open into a circular canal which surrounds the oesophagus at the base of the lophophore.
On the surface of the funnel-shaped lophophore are numerous ciliated grooves, and each of the tentacles in the tentaculated forms has a similar groove directed towards the mouth.
A so-called heart lies on the dorsal surface of the oesophagus; it is closed behind, but in front it opens into a circumoesophageal ring, which gives off vessels into the lophophore and tentacles.
The contraction of this heart, which is not rhythmic, brings about the expansion of the tentacles and lophophore.
There is, however, a considerable amount of resemblance between the lophophore of Phoronis australis, with its spirally twisted ends, and that of a typical Brachiopod; nor do the structural details of the adult Brachiopods forbid the view that they may be related to Phoronis.
It will be noticed that the lophophore of Phoronis is, on this assumption, a derivative of the collar just as it is in the Pterobranchia.
This tuft of tentacles is called the lophophore and can be retracted quickly by a strong muscle fixed into the envelope.
It has, moreover, been shown (see especially Goodrich, 5) that shortly before its metamorphosis, Actinotrocha develops a coelomic space which lies immediately in front of the oblique septum, and gives rise later to the cavity of the lophophore and tentacles.