PHYLUM ECHINODERMATA

Question 1

Body symmetry of the crinoids, asteroids and ophiuroids

Answer 1

Pentaradial symmetry

Question 2

Origin of the name of the phylum Echinodermata

Answer 2

Porous, calcareous dermal ossicles

Question 3

How are the ossicles arranged on the different classes of the echinoderms?

Answer 3

As flexible strutwork (Asteroidea)
Interlocking chain (ophiuroid and crinoids)
Rigid test covered with movable spines (echinoids)
Small and isolates (holothuroids)

Question 4

The porous plate where the water enters the water vascular syste

Answer 4

Madreporite

Question 5

Connects the madreporite and the ring canal

Answer 5

Stone canal

Question 6

Particla feeding of the crinoids

Answer 6

Mucous-covered podia on pinnules of feather-like arms

Question 7

How does ophiuroids capture suspended particles?

Answer 7

With mucus-covered podia or spines

Mucus net

Question 8

How does holothuroids capture suspended or deposited particles?

Answer 8

With large branched, mucus covered tentacles

Question 9

Scraping device of the regular echinoids used to feed on algae and encrusting invertibrates

Answer 9

Aristotle’s lantern

Question 10

Tripartite ceolom exhibited primitively by early larva

Answer 10

Axocoel
Hydrocoel
Somatcoel