How does a Proterospongia move?

How does a Proterospongia move?

It consists of a number of cells embedded in a jelly-like matrix. The flagellated cells with the collar structures move the colony through the water, while the amoeboid cells on the inside divide into new cells and so help the colony grow. Proterospongia itself is not the ancestor of sponges.

How do Proterospongia get energy?

The flagellum propels swimming cells through the water column and creates water currents through the microvilli, which trap foodstuff such as bacteria and detritus.

How do Choanoflagellates eat?

They eat by entrapping bacteria and detritus into the collar by moving its flagellum and then engulfing the prey via endocytosis. In this manner, choanoflagellates are similar to animals in that they digest their food internally.

What is the connecting link between porifera and Coelenterata?

(2) Ctenophora and Platyhelminthes.

How do Choanozoa reproduce?

Choanoflagellates are capable of both asexual and sexual reproduction. Movement of the flagellum creates water currents that can propel free-swimming choanoflagellates through the water column and trap bacteria and detritus against the collar of microvilli, where these foodstuffs are engulfed.

How do choanoflagellates reproduce?

With their characteristic collar surrounding the flagella, choanoflagellate cells are easy to recognize. Choanoflagellates reproduce asexually through binary division; sexual reproduction methods are not known.

Why are choanocytes evolutionarily important?

By cooperatively moving their flagella, choanocytes filter particles out of the water and into the spongocoel, and out through the osculum. This improves both respiratory and digestive functions for the sponge, pulling in oxygen and nutrients and allowing a rapid expulsion of carbon dioxide and other waste products.

What are the closest relatives of sponges?

Yet choanoflagellates must have existed on the Earth since the Late Precambrian, because they are the closest living protist relatives of the sponges, the most primitive metazoans.

What makes choanoflagellates unique?

Choanoflagellates are capable of both asexual and sexual reproduction. They have a distinctive cell morphology characterized by an ovoid or spherical cell body 3–10 µm in diameter with a single apical flagellum surrounded by a collar of 30–40 microvilli (see figure).

What separates animals from choanoflagellates?

There are striking physical resemblances between choanoflagellates and certain animal cells, specifically the feeding cells of sponges, called choanocytes. These similarities indicate that the unicellular ancestor of animals probably had a flagellum and a collar, and may have been much like a choanoflagellate.

Why is Balanoglossus linked?

Balanoglossus is the connecting link between chordates and non-chordates. Because notochord and pharyngeal characteristics are found in Balanoglossus. Hence it is the connecting link between chordates and non-chordates.

What are the connecting link between living and nonliving things?

Viruses are regarded as the connecting link between the living and non-living things as they possess living as well as non-living characters.

Is the Proterospongia a free living flagellate?

Proterospongia: Proterospongia (Fig. 22.7) is a free-living flagellate. It has a gelatinous matrix of irregular shape in which many zooids are embedded forming a colony. A zooid is an oval cell with a transparent collar at one end through which a flagellum comes out, these collared zooids are embedded on the outside.

What kind of state does Proterospongia live in?

Based on this description, Proterospongia alternates between colonial and swimming and adherent solitary states. Leadbeater’s 1983 description resulted in the consolidation of Choanocea perplexea and Proterospongia choanojuncta species into Proterospongia choanojuncta.

What kind of cell structure does a Proterospongia have?

Members of Proterospongia have the typical choanoflagellate cell structure characterized by a cell body 5-10μm in diameter with a 20-30μm apical flagellum surrounded by a collar of 15-25 actin-filled microvilli.

How are proterospongias different from other codonosidaes?

As a member of the Codonosigidae family, Proterospongia have only a fine investment that is indistinct by light microscopy or completely lack an outer-covering. Proterospongia species are distinguished by colony morphology, which vary from simple chains of cells to striking astral assemblages.