These important macromolecules act as catalysts to help carry out the thousands of chemical reactions that take place in cells. what is this macromolecule? a: lipid - hormone
b: protein- enzyme
c: nucleic acid - RNA
d: carbohydrate- cellulose

Which of the following best describes homeostasis? a. keeping the internal environment in a stable state b. keeping the external environment in a stable state c. beneficial characteristics resulting from mutation d. reproduction that results in offspring identical to the parent.

This part insulates the reaction chamber from the transfer of heat to or from the surrounding environment

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