I think the answer is "viruses can only multiply within a living cell." the other ones don't really sound right. but i'm not absolutely sure.
Answer:
B) expression of inappropriate gene products
Explanation:
Most of the cancers are caused when a normal gene that code for one or other proteins involved in the regulation of the cell cycle is mutated. The mutated gene may cause the production of the faulty gene products. For example, the overproduction of products of the protooncogene that push cells through the cell cycle leads to tumor formation. Likewise, when the tumor suppressor genes are not able to produce enough product to prevent progression through the cell cycle, cancer may develop.
All plant and animal groups existing together and the physical factors with which they interact compose an ecosystem<span>.</span>
I have no idea what that means but the answer is b
Answer:
They speed up chemical reactions. Without them you wouldn't be alive. They break down macromolecules, and also lower the amount of energy needed for a chemical reaction to happen.
