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2

First, you are misapplying Bernoulli's law. At each point, Bernoulli's law says that $$\text{constant}=P+\frac{\rho v^2}{2}$$ But remember, that constant is not constant in time for unsteady flows; it is constant in space. To make use of Bernoulli's law, we should consider two different points in the fluid flow. I will call the one closer to the aorta &...


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As far as we know so far, biology isn't able to break any laws of physics. However, biology isn't passive: biological systems react to changing environments to maintain some level of homeostasis. Arguably this is one of the defining characteristics of life. If you narrow the aorta, you will always get compensatory changes. Ultimately, the circulatory system ...


2

Physics/Chemistry aside, as @mimat and @aliential awesomely explained, it's always good to keep in mind that cancer, in general, is a statistics game, in the sense that at any time, there's a cell suffering mutation in your body, and it is not manifesting as cancer simply because your body evolved to deal with those situations. You can take a walk on the ...


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There are very many photochemical reactions: Up to 50–100 mutagenic reactions on DNA per second might occur in a skin cell during exposure to sunlight, but are usually corrected within seconds by photolyase reactivation or nucleotide excision repair. (That's just DNA, excluding O2 and other cell constituents) chemist ref and wiki ref Molecules that absorb ...


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Rather than 'breaks' caused by high energy radiation, UV radiation causes chemical modifications of the bases ('letters') that make up DNA. There are four bases in the DNA alphabet abbreviated to A,T,G or C belonging to two classes. A & G are guanines while T & C are pyrimidines. When you have pyrimidine bases next to each other on a DNA strand, they ...


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