Cytokinins _ 1.are naturally produced by plants 2.are used by Christmas tree growers 3.are primarily found in roots and fruits 4.all of the above

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.

if you look up in the top right corner you'll see your current profile picture, click than click "view profile" you'll be able to change it there.

the correct answer is 2 and 4