The correct terms to fill in the blanks would be contracts and dilates. In stressful situations, the sympathetic nervous system contracts the arteries of the circulatory system resulting to the dilation of the pupils of the eyes. Also, during these situations, the blood sugar levels are raised since the hormones for stress kick in to combat the stress which in turn raises the blood sugar.
In order for natural selection to take place we must have "variety in a population". This variety of traits is what allows natural selection to "pick" the most favorable traits.
Answer:
Personality.
Explanation:
The mental disorders affects the thinking ability of the individual. The mental disorder individual shows abnormal behavior in the society and might feel anxiety or feel awkward among the people.
The personality disorder is a type of the mental disorder in which the individual have unhealthy thinking level. This disorder affects the social status and his personality in the society. The occupational functioning become improper and requires the proper medical treatment.
Thus, the answer is personality.
Using the fossil record, you can categorize species based on analogous or homologous structures