Answer:
Dear
Anthony,
Stress
(the way that you feel when pressure is placed on you).
Worry
(an emotion in which a person feels anxious or concerned about a real
or imagined issue).
Unknown
and strange situations.
Anxiety
(a normal reaction to stress).
An increase
in sympathetic nervous system stimulation causes the heart rate to
increase.
Stimulation
of the sympathetic branch of the autonomic nervous system prepares
the body for emergencies: for "fight or flight".
Stimulation
via the cardiac beta-1 receptors causes the heart rate to increase.
Actions
of the beta-1 receptor include:
-Increase
heart rate
-Increase atrial cardiac muscle contractility
Catecholamines
stimulate cardiac contractility through beta(1).
Catecholamines
are sympathomimetic "fight-or-flight" hormones that are
released by the adrenal glands in response to stress.
