The two types of global food webs are the terrestrial and aquatic food webs.
Terrestrial food webs are located or start on land while aquatic food webs are located or start on waters. In this case, these are two connected when one consumer from the other realm becomes part of the food web of the other.
The nosepiece rotates to easily change the magnification. It holds two or more objective lenses that hold different degrees of augmentation power. This allows the person using the microscope to locate and detect different objects using a lower power lens and then examine the objects more closely with the high power one. There would only be one level of magnification if it didn't have a nosepeice .
Three reasons for cells to undergo mitosis are
-Growth
-Repair damaged cells
-Replace dead cells
Seeing that our species is constantly evolving, maybe it is starting to get more uncomfortable to walk on all fours.