The hydraulic skeleton is composed of muscle and fluid.
Answer:
A. pH relates to relative acid-base ion balance in a solution
Explanation:
PS. The ocean is slightly alkaline ;)
The major evidence that the evolution is still ongoing is mutations that occur. Those changes at gene level happen by chance during the process of copying DNA and change through the populations over time. Individuals who reproduced can pass that mutation to their offspring. When carriers with a specific mutation are better able to survive and reproduce, natural selection will favor them. That is the way of new variant to be passed down and spread through the population.
