The space between two neurons or between a neuron and a receptor organ is known as a

the sun d the answer is sun

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."

the cladogram shown here shows similarities and differences among several classes of vertebrates. anatomically, the four have limb structure as their common ancestor. we might separate the mammals from the other three classes because they a) divergent; do not lay eggs b) identical; are warm-blooded c) varied; a four chambered heart d) homologous; have mammary glands