Answer:
the light emitted by those devices is like a wake up call to the human brain. Specifically, the light prevents a hormone called melatonin from building up in the brain. It's this nightly production of melatonin that enables us to fall asleep.
Explanation:
the light emitted by those devices is like a wake up call to the human brain. Specifically, the light prevents a hormone called melatonin from building up in the brain. It's this nightly production of melatonin that enables us to fall asleep.
Your immune system uses a huge army of defender cells - different types of white blood cell. You make about 1000 million of them every day in your bone marrow. Some of these cells, called macrophages, constantly patrol your body, destroying germs as soon as they enter. This is your 'natural' or inborn immunity. But if an infection begins to take hold, your body fights back with an even more powerful defence of T- and B-cells. They give you acquired immunity, so that the same germ can never make you as ill again.
Cardiovascular System
In addition, the blood vessels that direct blood to the large muscles and the heart dilate, thereby increasing the amount of blood pumped to these parts of the body and elevating blood pressure. ... This long-term ongoing stress can increase the risk for hypertension, heart attack or stroke.
The system that prepares food for absorbtion into the bloodstream is the digestive food. It makes sure the food in the stomach is broken down.
