They are called essential because unlike the other ten unessential ones, they cannot be produced in our bodies. They must be obtained in our diet.
Although the actual questions are missing from your ask, here's how you can tell.
If the study will be messed up (added bias) through interaction with the subjects the study should be observational. For example if a biologists wanted to study the eating habits of wild birds in the tropics, they would need to do an observational study. if they did a controlled experiment, the birds will change their eating habits based on human interaction, thus making the study invalid.
If the study requires specific measurements, close monitoring, or contact and interaction with the subjects the study should be a controlled experiment. For example, if a scientist wanted to test out a new drug, the health of patients would need to be closely monitored.
Answer:
You should do the sport basketball, as it involves the body systems of the circulatory system and muscular systems.
Explanation:
<h2>Answer:</h2>
<u>The pituitary gland is called the master gland of the human body. </u>
<h2>Explanation:</h2>
The pituitary gland is called the master gland of the endocrine system present in the human body because this gland controls all the functions of many endocrine glands. The pituitary gland is no bigger than a pea, and is located at the base of the brain which hangs by a thin stalk from the hypothalamus.
Answer:
La membrana plasmática, también llamada membrana celular, se encuentra en todas las células y separa el interior de la célula del ambiente exterior. En bacterias y en células de plantas, hay también una pared celular que se une a la membrana plasmática en la superficie exterior. La membrana plasmática se compone de una bicapa lipidia que es semipermeable. La membrana plasmática regula el transporte de materiales que entran y salen de la célula.
Explanation:
