Match these items. 1. protective sacs (valves )
2. carries blood to the body (pulmonary)
3. carries blood to the lungs (heart chambers)
4. open and close (pericardium)
5. atria and ventricles (aorta)

Which kind of aquatic ecosystem does the photograph most likely show? a. marsh b. swamp c. lake d. river

What is the phylum of soft bodied animals with a true bosy cavity and a three part body consisting of a foot visceral mass and a mantle

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