Answer:
Because of the angle of the Earth relative to the sun. The higher the sun is in the sky, the higher the UV radiation level.
Explanation:
So, the lattitudes toward the poles that receive sunlight are at an oblique angle, with that being said, the amount of radiation is spread to a larger area than the equator.
Cyanobacteria are primitive organisms where chloroplasts are believed to be originated. Now, with the theory of endosymbiosis, this suggests that these organelle from cyanobacteria was engulfed by other organisms which has helped them process light with the help of chloroplasts.
The Challenger Deep is in the southern end of the Mariana Trench. It is estimated to be 305meters deep.
