What organic molecules functions to speed up biological chemical reactions?

Scientist have long study the earths climate by looking at which of the following? the earths orbit. the earths rock layers. the antarctic ice. the earths oceans.

Providing immunity by injecting the body with a weakened form a pathogen is known as

Asquirrel population lives in an area. over many years, a river in that area grows wider and stronger, eventually forming a canyon. the squirrel populations on the two sides of the canyon can no longer mate with each other and ultimately form distinct species. this is an example of