How does a parent bird usually incubate its eggs?

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.

When coal has reached it hardest, darkest form, it is called select one: 0 a. sub-bituminous b. lignite c. bituminous d. antrhacite next page

Q: a: in sexually reproducing animals, once fertilization of the egg takes place, the exists as a single cell until cell division begins