I believe that Calpurnia finds the food on the back porch.
A closed system is a system that makes no physical or chemical exchanges with its environment. Of these systems provided as choices (tree, human, clock, car), only a clock does not make exchanges with the environment, except for energy.
Therefore, of that list, only a clock would be a closed system.
Hope that helped! =)
One of the oldest arguments in the history of psychology is the Nature vs Nurture debate. Each of these sides have good points that it's really hard to decide whether a person's development is predisposed in his DNA, or a majority of it is influenced by this life experiences and his environment.
Answer:
Why is it thought that the majority of natural selection is stabilizing selection? Mutations produce extreme phenotypes, which are selected for. Artificial selection is the most common, which is a type of stabilizing selection. Most mutations are beneficial and produce intermediate phenotypes.
Explanation:
