19. Nervous System
Page 38 | Listen in audio
The nervous system is one of the most complex and fascinating systems in the human body. He is responsible for coordinating all activities in our body, from controlling vital functions such as breathing and heartbeats to performing complex tasks such as learning and memory.
The nervous system is made up of two main components: the central nervous system (CNS), which includes the brain and spinal cord, and the peripheral nervous system (PNS), which consists of all the nerves that branch off from of the CNS and extend throughout the body.
The CNS is the control center of the body, responsible for receiving information from the external and internal environment, processing it and sending appropriate responses. The brain is the most complex organ of the CNS, divided into several regions, each with specific functions. The spinal cord, in turn, is a long cylindrical structure that extends from the brain to the lower back, transmitting information between the brain and the rest of the body.
The PNS is made up of nerves that connect the CNS to the rest of the body, allowing communication between the brain and muscles, organs, and glands. The PNS is divided into the somatic nervous system, which controls voluntary movements, and the autonomic nervous system, which is responsible for involuntary functions such as digestion, breathing and blood pressure regulation.
Neurons are the fundamental cells of the nervous system. They are responsible for transmitting information in the form of electrical impulses, allowing fast and efficient communication between different parts of the body. Neurons are composed of a cell body, which contains the nucleus of the cell, and long extensions called dendrites and axons, which are responsible for receiving and transmitting information, respectively.
In addition to neurons, the nervous system also includes cells called glials, which perform a variety of supportive functions, including nurturing neurons, maintaining homeostasis, and protecting against infections.
The functioning of the nervous system is based on the transmission of electrical impulses between neurons. These impulses are generated by changing the polarity of the cell membrane, a process known as an action potential. When a neuron receives a strong enough stimulus, it generates an action potential that propagates along the axon to its terminal, where it releases neurotransmitters that can stimulate or inhibit other neurons.
Disorders of the nervous system can result in a variety of conditions, including neurodegenerative diseases such as Alzheimer's and Parkinson's disease, developmental disorders such as autism, and psychiatric conditions such as depression and anxiety. The study of the nervous system, known as neuroscience, is an area of intense research, with the aim of better understanding the functioning of the nervous system and developing new approaches for the treatment of its disorders.
In summary, the nervous system is a complex and dynamic system that plays a key role in almost every aspect of human life. Its study is essential for understanding the workings of the human body and for developing effective treatments for a variety of medical conditions.
Now answer the exercise about the content:
What are the two main components of the human nervous system?
You are right! Congratulations, now go to the next page
You missed! Try again.
Next page of the Free Ebook: