Question

Hyalonema is a .................... sponge.
a. Calcareous
b. Demospongia
c. Hexactinellida
d. Keratosa

Answer 1

Hyalonema is additionally called because the glass rope sponge. The Glass Rope Sponge may be a very unique species of sponges. These sponges haven't any organ system or tissues, can grow to be 6ft tall, and its skeleton is totally made of silica, giving this species their glass-like appearance. These sponges are usually found in deeper waters, and infrequently function as a shelter for invertebrates and fish. Furthermore, Glass Rope Sponges used to be very hip wedding gifts in Japan because of their elegant look and structure.

Complete answer:
In order to answer this question, we need to know about Hyalonema in detail.
Classification
Phylum – Porifera
Class – Hexactinellida
Order – Amphidiscophora
Genus – Hyalonema
Much of the body consists of syncytial tissue, extensive regions of multinucleate cytoplasmThe epidermal cells characteristic of other sponges are absent, being replaced by a syncytial net of amoebocytes, through which the spicules penetrate. Unlike other sponges, they do not possess the flexibility to contract. Their body also consists of three parts in total: the inner and outer peripheral trabecular networks, and therefore the choanocyte, which is employed for feeding purposes. The choanosome acts because the mouth for the sponge while the inner and outer canals that meet at the choanocyte are passages for the food creating a consumption path for the sponge.
One has a unique system for rapidly conducting electrical impulses across their bodies, making it possible for them to retort quickly to external stimuli. Glass sponges like "Venus' flower basket" have a tuft of fibers that extends outward like an inverted crown at the bottom of their skeleton. Glass sponges are different from other sponges in an exceedingly kind of other ways. as an example, most of the cytoplasm isn't divided into separate cells by walls but forms a syncytium or continuous mass of cytoplasm with many nuclei It belongs to the category of Hexactinellida.
It is a marine formation and located deep into the ocean. It is found deep within the sea. It’s a round or oval body with a spirally twisted root tuft. Its skeleton is of silicon amphidisc spicules. To produce sexually, the Glass Rope Sponge releases its sperm into the water to fertilize the eggs of a neighboring sponge. The eggs soon convert into a larvae, then rummage around for a surface that may allow it to grow into an adult sponge. In asexual mode, the Glass Rope Sponge goes through the method of budding. Because the sponge develops a bud that may eventually change into a brand new sponge, it stores new sponge-cells into a vesicle or sac. The sponge then releases this vesicle into the water before it dies, allowing the bud to transform a brand new sponge. Hexactinellid sponges are sponges with a skeleton made from four- and/or six-pointed siliceous spicules, often mentioned as glass sponges. They're usually classified together with other sponges within the phylum, but some researchers consider them sufficiently distinct to deserve their own phylum, Symplasma.
Therefore, the answer is c, Hexactinellida.

Note: The earliest known hexactinellida are from the earliest Cambrian or late Neoproterozoic. They’re fairly common relative to demosponges as fossils, but this is often thought to be, a minimum of partially, because their spicules are sturdier than spongin and fossilize better. Like the majority sponges, the hexactinellida draws water in through a series of small pores by the whip like beating of a series of hairs or flagella in chambers which during this group line the sponge wall.
The class is split into five orders, in two subclasses:
Class Hexactinellida
Subclass Amphidiscophora
Order Amphidiscosida
Subclass Hexasterophora Incertae sedis
Dactylocalycidae Gray, 1867
Order Lychnis Cosida
Order Lyssacinosida
Order Sceptrul Phora