Oncogenes result from turning on, or activating proto oncogenes. Proto oncogenes are genes that code for positive cell cycle regulators, so proto oncogenes code for proteins that turn on cell division. Proto oncogenes are normal genes, but when they are mutated, they become oncogenes. Oncogenes are expressed too much, which makes them turn on cell division too much, which is cancer.
The answer is C- Excretory system. Hope this helps :)
Answer:
DNA is the genetic information used to make proteins, and it contains the hereditary traits of organisms. There are two types of DNA: mitochondrial DNA, which you can only get from your mother, and nuclear DNA, which is a combination of both your ancestors' DNA.
Explanation:
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