Question

on your way home, you cut through the woods and think you see a bloody figure behind a tree. you turn away to run but feel yourself go limp and you slump in a faint. what happened in your body to cause these reactions? the sight of the bloody figure triggers adrenaline in your ____________ system to increase as you turn to run away. however, a sudden drop in your blood pressure slows the blood flow in the ____________ system to the brain and you faint. circulatory excretory nervous immune endocrine muscular

Explanation:

• When you see the bloody figure, the nervous system detects the threat. The endocrine system releases adrenaline (epinephrine) which is a hormone. Adrenaline causes the heart rate (in the circulatory system) to increase, preparing the body for a "fight - or - flight" response.
• A sudden drop in blood pressure affects the circulatory system. Blood flow to the brain (which is part of the nervous system's supply) is slowed. The brain needs a constant supply of oxygen - rich blood (delivered by the circulatory system) to function. When the blood flow is insufficient (due to low blood pressure in the circulatory system), the nervous system (brain) can't function properly, and you faint.

Answer:

1. Endocrine (because adrenaline is released by the endocrine system)
2. Circulatory (because heart rate is related to the circulatory system and blood flow to the brain is part of the circulatory system's function)
3. Nervous (because the brain is part of the nervous system and its proper functioning depends on blood supply from the circulatory system)