Question

question 2 (10 points)
which group includes sea stars, sea urchins, sea cucumbers, and sand dollars ?
a) cnidarians
b) sponges
c) annelids
d) arthropods
e) flatworms
f) roundworms
g) echinoderms
h) mollusks
i) chordates
question 3 (10 points)

Explanation:

Echinoderms are a group of marine invertebrates. Sea stars (starfish), sea urchins, sea cucumbers, and sand dollars all share key characteristics of echinoderms. These include a water - vascular system, radial symmetry (often in a five - part pattern), and an endoskeleton made of calcium carbonate plates. Cnidarians (like jellyfish) have stinging cells (nematocysts). Sponges are simple filter - feeding organisms with no true tissues in a strict sense. Annelids are segmented worms. Arthropods have an exoskeleton and jointed appendages. Flatworms are unsegmented and often have a flattened body. Roundworms are cylindrical and have a pseudocoelom. Mollusks have a soft body often protected by a shell. Chordates have a notochord at some stage of development (usually in the embryonic stage for non - vertebrate chordates).

Answer:

g) echinoderms