The sphincter (that which binds together) muscle at the end of the digestive tract is the:

The cluster of developing cells from conception until birth is called an

Which short-term environmental change is most likely to lead to ground shifting, landslides, and the collapse of buildings or roads? forest fires flooding earthquakes

Substances that can pass through cell membranes by diffusion include a. na ions. b. proteins c. glucose. d. oxygen.