Take a look at the two boxes below. Each box has the same volume. If each ball has the same mass, which box 1 or 2 would weigh more? Why?

Box 1.

Explanation:

The box 1 have the more mass because there are more number of balls present in the box while on the other hand, box 2 has less number of balls in the box. The volume of box boxes are the same as well as weight of the both boxes before placing of balls in it. Placing of balls changes the weight of both boxes because of the presence of different number of balls in each boxes that increases its weight.

the reason the two sea urchins don't compete with each other for food, resources, etc. is because the urchins have adapted to the environment but they have also adapted to each other. this is most likely because the genes of the sea urchins.

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.