When your math teacher was handing out the test, you noticed that your respiration rate and heartbeat increased, your palms got sweaty, and your hand shook a little. your pretest behaviors were triggered by the upon completion of the exam, your body returned to its normal state by way of the

My pretest behaviors were triggered by the sympathetic nervous system, while my body returned to its normal state by the way of the parasympathetic nervous system, after the test.

Explanation:

The sympathetic nervous system and the parasympathetic nervous system are part of the autonomic nervous system. The main function of the autonomic nervous system is to regulate the heart, kidneys, and liver which are not under voluntary control. The regulation of the body’s unconscious actions is executed through the sympathetic and the parasympathetic nervous system.

Upon exposure to stressors or threats, the sympathetic nervous system is triggered. Epinephrine and norepinephrine are then released, causing acceleration of the heart, constriction of blood vessels, increase in blood pressure, profuse sweating and other related responses against stress. The sympathetic nervous system controls all these involuntary responses that could be termed “fight-flight-or-freeze” response.

On the other hand, the parasympathetic nervous system initiates what is termed “rest and digest” response, which occurs immediately after the “fight-flight-or-freeze” phase response to stress is over. The body is returned to its normal state by the parasympathetic nervous system. The parasympathetic nervous system releases acetylcholine, which regulates the function of the body during a period of rest or recuperation.  

answer: the blood-brain barrier is a layer of specialized membranes and cell processes designed to keep undesirable substances from passing from the bloodstream into the precious tissues of the brain. while the blood-brain barrier does keep most bad things out of the central nervous system, it is not impermeable.

explanation: