4. Two products of the Krebs cycle are ATP and 02
ATP and CO2
ADP and H2O
H2O and CO2

organisms that are both used in toothpaste as well as cause malaria are protista and monera.

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.

nucleus

would be most reasonable answer tbh