Ants and aphids often live near each other. the ants feed on wastes produced by the aphids, and the aphids are protected from predators by the presence of the ants. what type of relationship is this?

How is the male reproductive system different from other body systems? it isn’t necessary to vital signs. it monitors other body systems, and adjusts if necessary. it transports items from one system to another. it is the only system that produces hormones in the male.

The first signs of cellular differentiation occur in the blastocyst. why is cellular differentiation important for the development of a fully formed human infant?

According to the cladogram, which organisms have roundworms as a common ancestor?