Which statement is true about the differences between plant and animal cells? A) Only plant cells have cytoplasm.
B) Animal cells are always larger than plant cells.
C) Plant cells have vacuoles, but animal cells do not.
D) Only plant cells have chloroplasts that help make food during photosynthesis.

organisms that lack symmetry are called asymmetrical and belong to phylum porifera/sponges.

organisms with specialized stinging cells belong to phylum cnidaria. stinging cells are called cnidoblast cells.

cnidarians show two morphological forms : polyp (sessile) and medusa (mobile)

filter feeding is observed in porifera members.  

alternation of generation is observed in coelenterata or cnidaria. there is alternation of asexual polyp form and sexual medusoid form. it is also referred as metagenesis.