What happened when two forces act in the same direction

They repel one another. I think

When two forces act in the same direction a few things can happen such as...

Explanation:

If the two forces are equal then there will be no movement but it the two forces are different, one being stronger the the strong one will over power the weaker one and the motion will move against it the weaker one causing it to move in the direction of the stronger, and of course there will be a bit of resistance.

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.