How could natural selection affect humans?

Explanation:

an example is the ability to endure the sugar, lactose, in milk. In many places of the world, people can't drink milk in light of the fact that their body turns off the intestinal creation of lactase, a chemical that processes the sugar in the milk.

the glands which are associated with each description is given below:

the atomic number of magnesium is 12. its nucleus must contain 12 protons and no electrons. the atomic number of an atom is determined by the number of protons.

magnesium is an electrolyte injection commonly used to treat low magnesium levels in your blood. it is also used to prevent or control seizures in women with preeclampsia or eclampsia.