Natural selection is based on four main principles: variation, overproduction, adaptation, and descent with modification. briefly explain how each of these principles is necessary for natural selection to occur?

Variation because if there aren’t different types, then it can’t occur
Overpopulation because then there can not be variation in the offspring
Adaptation because then some of the species have to adapt to the environment so the best traits can be chosen
And descent with modification, so the best types can survive

DNA replication is described as semi-conservative because each DNA molecule has one new strand and one original strand. contain one ring of carbon and nitrogen atoms. because the bases of DNA pair only in certain ways so each molecule contains the same information. two new DNA molecules form.

Explanation: