) Veins have different structures from arteries. State two features of veins and explain how these features enable them to function efficiently.

If scientists are wrong about earth's age based on radioactive material and the decay rates are really much faster, how would nuclear power plants be affected?

The green colored pigment in chloroplasts is? a. nitrogen b. chlorophyll c. chlorophorm d. chlorofloromethane

Which of the following explains why a tree is often used as a model to represent the principle of common descent