Answer to Question 1
Jitteriness and sleeplessness in high doses.
Increased risk of miscarriage.
Stimulates release of stress hormones.
Most widely used psychoactive drug.
More than half of Americans drink coffee daily.
Answer to Question 2
Many muscles in the body remain in a chronically contracted state because they are continuously receiving the message from the nervous system that they should be contracting in preparation for fight-or-flight. But they don't receive the signal from the nervous system that the threat has passed and it is safe to relax.
