When it gets cold, the accumulated water inside the pipes freezes, expands and creates extreme pressure.
If a portion of the grass was destroyed by wildfire, then the population of bison that feed on the grass will decrease. This is because there would be very little grass left for them to eat, and they don't eat anything else.
On the pH scale 7 is a neutral. Anything below 7 is acidic and anything above 7 is a base.
ANSWER:
Most types of cancer are believed to begin with a random genetic mutation. This is followed by mutations, which endow the cancer cells with properties allowing them to grow without normal controls to become a tumor.
Mutation is any change in the DNA sequence of a cell. Mutations may be caused by mistakes during cell division, or they may be caused by exposure to DNA-damaging agents in the environment.
Genetic Mutations that lead to cancer cell formation can occur in two forms:
1. GROWTH-PROMOTING GENES are commonly mutated in cancer cells, becoming SUPER-ACTIVE and producing cells that are too strongly stimulated by growth receptors.
2. Mutations can INACTIVATE the genes that suppress cell proliferation or those that signal the need for apoptosis. These genes are known as TUMOR SUPPRESSOR GENES.
