Answer: The Tigris-Euphrates river system, where Mesopotamia started, was an area prone to frequent flooding. The flooding deposited valuable silt onto the land and enabled crops to be grown and harvested in surplus. This was the first time farmers had an excess of what they needed. The surrounding land was devoid of most other raw materials, such as wood, stone and metal. To get these materials, the early Mesopotamians resorted to trade. At these gathering hubs, people began constructing buildings, which formed the basis for the first cities to appear and helped civilizations continue to develop.
Answer:
through the process of respiration
Explanation:
<span> There will be fewer natural resources available for future generations.
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Answer:
CHK2, p53, p21, cell cycle progression.
Explanation:
In a normal cell with no LFS mutation, during the G1 stage of cell cycle progression, the CHK2 activates if there is damage in the DNA. CHK2 activates p53, which is a tumor suppressor protein that will hold the cell cycle in G1/S until the DNA is repaired. The p53 protein activates p21, a protein that binds to CDK2 and stops the cell cycle. The cell cycle will continue once the damage is repaired.