There are those who say that human behavior is another aspect of our biological design, of what causes us to be born and develop as we do. In a sense, this is true: all our mental activity is, in essence, the product of a set of nerve cells that capture information from the senses, process it, and send orders to the muscles.
However, the nervous system is not the only component that allows us to relate to what surrounds us (and to others) as we do. The endocrine system is also involved in this , through its hormone emission and uptake mechanisms. In the following lines we will see what the endocrine system is, what its parts are, and what function it has in the body.
The nervous system is a network of organs and cells that have evolved to produce rapid changes in the state of a living being, depending on the situation, maximizing the chances of an option or reflex appearing that is useful in that context.
However, sometimes there is a need for these changes to be more sustained and to affect not only the parts of the organism that are involved in a specific action (for example, the arm), but also many target organs, more or less at the same time. Same time. That is why The nervous system is complemented by what is known as the endocrine system
The endocrine system is, in summary, a set of organs and cellular tissues that secrete types of substances called hormones, which travel through the bloodstream and serve to regulate different biological processes.
Difference between the functioning of hormones and that of neurons
Unlike what happens with neuronal activity, the effects that the endocrine system exerts on the body are not usually immediate and take longer to fade, since from the moment “the order” is given to release hormones until they reach their destination several seconds pass.
Furthermore, another difference between the endocrine system and the nervous system is that if in the former the order transmitted electrochemically can reach a specific place in the body, the hormones are never predestined to reach a certain place at a certain time. , but when released into the blood, flood many parts of the body almost at the same time some of these particles reaching their target organ purely as a matter of probability.
On the other hand, a single hormone release has sustained effects on multiple parts of the body at once. This is no coincidence, because if something characterizes the endocrine system, it is that through its regulation of hormone levels it usually achieves a balance (homeostasis) between the different parts of the body, all of them adapting to the same situation, but each one to its own. his way.
For example, In a dangerous situation, adrenaline is secreted in greater quantities by the endocrine system, causing both the heart to beat faster (to react quickly) and the capillaries close to the skin to become constricted, possibly so that little blood is lost in the event of injuries.
The fact that the work of hormones and neurons go so hand in hand has meant that one can even speak of a neuroendocrine system : the nervous system deals with work in the very short term (thousandths of a second), and the endocrine system achieves effects that take a little longer to arrive but last longer and are consistent with the work of the nerve cells.
His parts
Between the endocrine organs and the parts of the body in general that are involved in the endocrine system the following components stand out.
1. Pineal gland
Located in the lower part of the brain, the pineal gland or epiphysis acts as a bridge between the nervous and endocrine systems. Among the hormones it secretes, melatonin stands out involved in the regulation of the sleep-wake rhythm.
2. Pituitary gland
This part of the body, which is also called the pituitary gland, is also located in the lower part of the brain. It is very important, since it secretes many types of hormones and indirectly affects the secretion of others, since it stimulates other glands located in different parts of the body, including the thyroid.
It fulfills many functions, and Among them, the regulation of several biological processes stands out linked to reproduction and sexuality. For example, it allows the ability to breastfeed to appear, as well as the maturation of eggs and the creation of sperm. Its role in growth is also very important, since it secretes growth hormone.
3. Adrenal gland
These glands are located on each of the two kidneys that the human body has, and their role in the endocrine system is linked to the regulation of stress states , fundamentally those that have to do with fight or flight behaviors. For example, they can increase blood volume, stimulate energy available for immediate expenditure, and inhibit biological processes with long-term objectives, such as the inflammatory response.
The hypothalamus is one of the most important parts of the brain, and initiates several mechanisms for the release of many different types of hormones from various glands, based on the capture of nerve signals. For it, secretes hormones from the corticosteroid and catecholamine groups
5. Thyroid
The thyroid is a large gland located in the neck. Secretes calcitonin, triiodothyronine and thyroxine hormones that intervene in the regulation of metabolism and oxygen consumption, as well as in the generation and regeneration of bones.
