The cell can be thought of as a system. A system usually consists of many parts that work together. A system will not function as well if
one part is not working properly. We as humans use systems every
day, such as a bicycle. Some of the parts in your bike are the gears,
the brakes, and the materials used to make the bike frame. What
would happen to a bicycle if one of the parts, such as the brakes,
stopped working?

The bicycle would become inoperable. For example, if the brakes stopped working the bike would not be able to work optimally. In the same vein, if the chain was broken you would not have enough motion to move forward. A system is important because it relies on all parts to function. I would not be able to function without a brain and so forth.

Explanation:

This shouldn't be under Geography.

answer; ///i believe the correct answer to the above question is; ///(drainage basin;

they were destroyed coming out of the civil war but after he war they were booming. if you need an in-depth answer follow up with me  

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