What do veins have that arteries and capillaries do not?

a. valves
b. skin cells
c. extra thick
d. chambers

What is the name for a substance formed in a chemical reaction

The blue particles in this image are able to cross the cell membrane through simple diffusion. how will they be transported? outside the cell inside the cell o a. the substances will move directly across the membrane from outside the cell to inside the cell. b. the substances will move through channels in the membrane proteins from outside the cell to inside the cell. o c. the substances will move through channels in the membrane proteins from inside the cell to outside the cell. o d. the substances will move directly across the membrane from inside the cell to outside the cell.

As an asteroid comes close to earth, it's name will change to? apex