Answer:
For natural selection to occur, it is true that there must be genetic variation in the population.
Explanation:
According to evolution, natural selection implies the changes that occur in the genotype of a species, due to the effect of environmental factors, and which guarantee its survival through adaptive evolution.
For natural selection to occur, three fundamental conditions must exist:
A trait that can be inherited from one generation to another.
The trait is subject to variability between subjects of the same species.
Genetic variability can determine the possibility of reproductive success and survival.
Therefore, a necessary factor for natural selection to occur is that genetic variability exists in the population.
Answer:
the answer should be DNA REPLICATION
<span>The Periosteum is the membrane that covers a bone.Generally Periosteum is a thick layer of vascular connective tissue concealing the bones with the exception of at the surfaces of the joints. Periosteum acts like the skin of the bones.Periosteum plays an important role in bone growth and maintenance.</span>
That would be the Northern Hemisphere if I remember.
The digestive system is necessary for the body's health because it breaks down the food we eat into small pieces that can be absorbed by the body. Without the digestive system, we would not receive all of the nutrients from food.