Which of the following is NOT a characteristic of vein. A) Valves prevent backward flow of blood
B) returns blood to the heart
C) Walls are one cell thick
D) contracts to push blood along

What are some aquatic organisms that live in cold water temperatures?

In which terrestrial biome can you find trees that produce cones instead of flowers and needles instead of leaves? have trees that produce cones instead of flowers and needles instead of leaves. the latitudes in this biome have evenly distributed precipitation throughout the year. is it high or low

Where are the strongest jet streams located?