Cual es el estímulo, receptor, el centro de control, el efecto y la respuesta de retroalimentación del nivel de oxígeno en sangre

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.

population. population is the number of people or animals in a particular place. an example of population is over eight million people living in new york city.

here is your answer hope i .