In a cell, there are several parts of it that are there to stop this from happening. Cancerous cells do not have the genetic code to stop growing and reproducing. A regular cell will actually destroy itself it there is a mutation. If it does not get destroyed, it could potentially be tumorous, then it could eventually be cancerous.
<span>Collin often experiences a "runner's high" during his daily three-mile run. this is most likely produced by endorphins.
Endorphins are related to a group of hormones which are secreted within the brain and the nervous system, it is like morphine chemicals which are produced. It is mostly produced when you exercise a lot, run high or stress etc.</span>
They don't reproduce, as far as I know. They are produced in bone marrow.
The lining of the back of eye containing two types of photoreceptor cells - rods - sensitive to dim light and black and white - and cones - sensitive to colour. A small area called the fovea in the middle of the retina has many more cones than rods.
The food chain is a system in which food is connected with the ecosystem. Ex:composers, producers, decomposers,etc.