Explain why psychologists are concerned with human biology.
I think that psychologists feel a need to know the biological function of the brain in order to better understand how people think and act in different situations. They also need to have an understanding of how medications can impact the brain and the ability of it to function.
It is impossible to escape the fact that how we think and what we do and our motivations for committing certain acts are impacted greatly by our biology, or physical make up. This is why both sociologists and psychologists are fascinated by the science of the human body. Of course, the biggest dilemma is the whole question of whether our genes or heredity is more of an influence than our environment or our context. Such issues are hotly debated in the social sciences.
Another reason for this is that a knowledge of the biology of the brain, for example, can help psychologists to measure the impact of various stimuli on a person's brain. I was just reading an article about the insanity defense and how attitudes towards it are changing because of changing understanding of what is happening in the brain.
Psychologists can expose a person to various stimuli and then see how the brain reacts to those stimuli (as opposed to trying to look at the person's facial responses or the person's actions). This can help them understand if the person is reacting normally to the stimuli or if they might have some form of mental illness. This sort of testing would not be possible if the psychologists did not understand biology.
Psychologists are very concerned with human biology for numerous reasons. First of all, psychology is very scientific and deals specifically with the mind. Generally speaking, psychologists attempt to explain why people think and act the way that they do. The human thought process is very physiological and there are many chemicals that flow through the brain. For example, these chemicals control things such as impulses, moods, etc. Some forms of mental illness are also caused by an imbalance in these chemicals. If psychologists were not concerned with these things, then they would not be able to thoroughly understand the human thought process.