Biotic:
-predator
-competition(relationsip)
abiotic:
-sunlight
-water
Valves, they are like flaps of muscle that keeps the blood in its place util its ready to be pumped along.
In order to study the formation of cancer cells, you should study the life cycle of normal cells as cancer cells are abnormal cells.
Actually, Normal cells grow, divides and died after an interval of time. And when this process is break down, cancer cells begin to form. They are usually old cells which don't die after their life cycle.
Hope this helps!
A larger piece of plastic waist is worse
