Question

question 5 (10 points)
which organism lacks body symmetry and tissues?
a) cnidarians
b) roundworms
c) arthropods
d) flatworms
e) sponges
f) annelids
g) mollusks
h) chordates
i) echinoderms

Explanation:

• Cnidarians (like jellyfish) have radial symmetry and tissues.
• Roundworms, arthropods, flatworms, annelids, mollusks, chordates, and echinoderms have either bilateral or radial symmetry and tissues.
• Sponges (phylum Porifera) lack true tissues and have an asymmetrical body plan (in most cases, some may show a rough sort of radial - like appearance but still lack the defined symmetry and tissue - level organization of other groups).

Answer:

e) sponges