The tiny hollow air sacs in the lungs where gas exchange takes place are the?

What type of fossil fuel is made from trees, ferns, mosses, and other marsh plants?

A force that causes particles to move or change

Many mosquito populations today are resistant to pesticides that were historically effective. This pesticide resistance arose in these populations because:a) the pesticides caused mutations in the DNA of mosquitoes that conferred resistance

Is phrenology science or pseudoscience

What type of structures have the same structure or function, but they do not share a common ancestor such as the wings of an insect and the wings of a bat.

What change caused multicellular life to form

Why type of physical weathering is caused by the expansion of water?

Describe the structures that form the outside of a prokaryotic cell. Tell whether each structure is common to all prokaryotes

What are hormones made from cholesterol called?

How did earth cool down enough to sustain life