Ionic bond is the correct answer
<span>Sponges have biradial symmetry, canal system, skeletal system, osculum as an outlet of water.
Moreover, they have pores in the body to let water come in. In addition,they also have choanocytes,gemmules etc and they are diploblastic. Whereas these functions are not found in protists.</span>
B) A twist or tear in a muscle
:)
Explanation:
A keystone species is an organism that helps define an entire ecosystem. By keeping populations of mussels and barnacles in check, this sea star helps ensure healthy populations of seaweeds and the communities that feed on them—sea urchins, sea snails, limpets, and bivalves.
Without an external energy source, friction stops the car..
