When testing a hypothesis, scientists use repeated trials and replication to make sure that they get the same answer each time, and that it isn't just a lucky guess the first time. They need be sure that the answer to their hypothesis is 100% the same every time.
Tumor suppressor genes encode for proteins that inhibit or slow the progression of the cell cycle through a specific stage.they also encode for check point control proteins that arrests the cell cycle if the DNA is damaged or the chromosomes are abnormal. Mutation in the tumor suppressor genes that cause a loss or decreased function would lead to uncontrolled cell cycle leading to abnormal proliferation and the cell may become cancerous.
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<span>Many sexually active american adolescents fail to avoid pregnancy because they are not educated on contraceptive methods. </span>