A major side effect that stress can cause on the gastrointestinal system is .A. diminished levels of gastrin, leading to constipationB. elevated levels of gastrin, causing stomach ulcersC. elevated levels of cortisol, causing overeatingD. diminished levels of cortisol, causing weight loss

C. elevated levels of cortisol, causing overeating.

Explanation:

Stress releases the hormones and also the effects of high-fat, sugary "comfort foods" push people toward overeating.

Stress can possibly shut down appetite. When the body is stressed, the nervous system sends messages to the adrenal glands atop the kidneys to pump out the hormone adrenaline. Adrenaline helps to trigger the body's fight-or-flight response, which is a revved-up physiological state that temporarily puts eating on hold.

But if stress persists, it's a different story entirely. The adrenal glands release another hormone called cortisol, and cortisol increases appetite and may also ramp up motivation in general, including the motivation to eat. Once a stressful episode is over, cortisol levels should fall, but if the stress doesn't go away — or if a person's stress response gets stuck in the "on" position — cortisol may stay elevated, causing overeating.

C. Elevated levels of cortisol, causing over heating

Explanation:

The stress hormone is called cortisol.  Once the body is stressed , the adrenal glands secrete high amounts of cortisol into the blood stream. This can lead to increase in the heart rate and the blood pressure. High cortisol levels in the blood reduce the insulin levels, causing overeating. This is because even though glucose is present in the blood, the cells are still starved of it.  Causing the sensation of hunger during stress periods.

This makes option C correct.

Option A is wrong.

Gastrin is not the stress hormone. it  is a hormone which stimulates secretion of gastric juice and is secreted into the bloodstream by the stomach wall in response to the presence of food.

Option B is also wrong

Gastrin is not the stress hormone.

Option D is wrong

Stress increases the level of cortisol secretion, rather than reduces it.

the oxygenated blood then leaves the lungs through pulmonary veins, which return it to the left heart, completing the pulmonary cycle. this blood then enters the left atrium, which pumps it through the mitral valve into the left ventricle. from the left ventricle, the blood passes through the aortic valve to the aorta.

deoxygenated blood leaves through the right ventricle through the pulmonary artery. from the right atrium, the blood is pumped through the tricuspid valve (or right atrioventricular valve), into the right ventricle.