Stress
Stress Objectives
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Explain what stress is, including examples of short-term and long-term stress events.
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Describe the impacts of adrenaline (epinephrine) and cortisol on the body.
- List factors that can reduce the potential impacts of a stress response.
Stress has many meanings. In a medical sense it refers to a physiological response to external and/or internal cues.
People respond very differently to external variables. Some people will watch this spider and be distressed by the legs and movement; others will think it is adorable. Some of these responses are innate (genetically determined) and other are learned through experience.
Stress-inducing occurrences and our responses can be be positive. We may pay better attention, feel motivated, and get things done.
Unfortunately, stress responses can also be harmful, particularly if chronic and un-managed.
What are the endocrine organs that sit on top of each kidney? _____
Now we are going to see how these organs play a critical role in stress management.
This microscopic specimen helps in visualizing the difference between the adrenal cortex and the adrenal medulla.
We have all experienced an “adrenaline rush.” Re-live what it feels like.
Consider why these physiological responses would be significant in an actual emergency.
The stress response occurs along two pathways. In short-term stress, senses send information to the brain, and the brain sends a signal through the spine and nerves directly to the adrenal medulla. The adrenal medullar than releases ___, the “emergency” hormone.
In response to long-term stress like starvation or chronic bursts of short-term stress events, the hypothalamus triggers the pituitary gland to release a hormone that increases cortisol production in the adrenal cortex. High levels of cortisol can cause a negative feedback loop that reduces this stimulation by the hypothalamus. However, continual feedback “desensitizes” the hypothalamus’ response and cortisol keeps getting produced.
Cortisol has wide-reaching impacts on the body that would be helpful if an individual was facing starvation. Does cortisol increase or decrease overall metabolism? ___
In addition to cortisol and epinephrine, the adrenal glands release other important hormones. The mineralcorticoids and glucocorticoids mediate inflammation, a topic explored in the week 9 module.
Many people assume that stress leads to hypertension. It is not that straightforward. What is understood is that a balance of healthy behaviors correlate with lower incidence of hypertension.
Many factors are not under our control, but some are. Consider the impact of carving out a small corner of space intended to reduce stress-inducing triggers.
One of the external factors that contributes to stress is not having enough time to complete desired activities. There are natural times events like day/night and the seasons, but our perception of time can be creatively managed to a point.
The next section introduces metabolism, cellular activity within the body.
Check your knowledge. Can you:
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explain what stress is, including examples of short-term and long-term stress events?
-
describe the impacts of adrenaline (epinephrine) and cortisol on the body?
- list factors that can reduce the potential impacts of a stress response?