The three major issues that cut across psychology are stability versus change, rationality versus irrationality and nature-nurture issue.
Stability versus change deals with the issue of whether human beings change as they grow older or they remain essentially the same.
Rational versus irrationality illustrates the disparity between a human's mind ability to perceive and interpret correctly or incorrectly.
Nature - nurture issue centered on the relative contribution of genetic inheritance and environmental factors to human development.
Answer:
Ozone layer saves the earth from the ultraviolet rays of sun which is harmful for earth. It is situated jn upper atmosphere and saves earth. But thus chlorofluorocarbons destroys the Ozone Layer in the atmosphere.
The amount of hyaline cartilage in the embryonic skeleton is much higher than in a child. This is because the embryonic skeleton will still go calcification as the embryo ages to fetus and eventually to being a child to adulthood.
DNA acts as a sort of set of instructions for building an organism.
In that way, different types of organisms--plants, animals, bacteria, etc.--can all be differentiated through their DNA because it is directly linked to how they function.