Which organism appeared on earth first?

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.

Indica el nombre y la fucion de los vasos sanguineos que entran y salen de los riñones

Is genetic diversity the same as genetic variation?