A delta is formed by constructive erosion.
The correct answer is fight or flight.
The fight or flight response also called acute stress response, is a physiological response to a perceived attack, threat or in general any stressful event. This reaction consists the first stage of the general adaptation syndrome, which is the mechanism that regulates the response to stressful situations.
This response consists of an activation of the autonomic nervous system and a cascade of hormones, including catecholamines, cortisol, estrogen, testosterone, and dopamine. This hormonal cascade results in many physiological changes which prepare the body for action.
Answer:
Why are embryos used in medical research?
Stem cells can be obtained at the early stages of embryo development; these cells are called human embryonic stem cells (hESC). They also could be used in research to develop drugs to treat serious diseases, or to repair organs following a stroke or heart attack.