The brain is an essential part of the nervous system

The brain is an essential part of the nervous system



It is located in the cranial capsule and is surrounded by meninges: hard, arachnoid and soft. The mass of an adult's brain is mainly 1350 g, but a person's intellectual abilities are not proportional to the weight and size of the brain.

The medulla oblongata, the Varoliev bridge, and the midbrain are collectively called the brainstem. The central canal of the spinal cord continues in the brain, but expands and forms four cavities - chambers of the brain, which are filled with cerebrospinal fluid.

The brain is the most complex organ of the human body. It is part of the central nervous system and is located in the skull. It controls all vital activities necessary for the survival of the body. All human emotions are controlled by the brain. It also sends and receives countless signals from all other parts of the body and the external environment. The brain makes us conscious, emotional, and intelligent beings.

There are two types of cells in the brain: nerve cells and glial cells. Nerve cells (neurons) differ from other cells in that they have the ability to conduct nerve impulses. The human brain consists of about 10 billion nerve cells. Each nerve cell consists of a body of neurons and two types of appendages: dendrites and axons. The body of a neuron (soma) contains the nucleus (in which DNA is located), the endoplasmic reticulum and ribosomes (for protein synthesis) and mitochondria (for energy production) - it performs all the functions necessary for cells to survive. Axons and dendrites are used to communicate between cells. Dendrites are short branched appendages that stimulate the body of a nerve cell. An axon (neurite, nerve fiber) transmits stimuli from the body of a neuron to the next neuron, it can be covered with a special membrane of glial cells (oligodendrocytes), which accelerates the flow of impulses through the axon.Each nerve cell is connected to about 10,000 other nerve cells through synapses (the connection between the axons of one cell and the dendrites of another cell). Glial cells (glia) perform a number of functions that ensure the survival and proper functioning of nerve cells: supportive (their extensions create a supportive network of brain tissue), insulating (in the area of synapses they perform electrical isolation), protective (can be transformed into macrophages), transport (transport nutrients from blood vessels to nerve cells of the brain), play a role in local homeostasis, perform phagocytosis of unnecessary substances, build the myelin sheath of axons. There are about 10 times more of them in the brain than there are nerve cells. We can distinguish between lighter and darker areas of the brain. The dark part is a gray mass consisting of nerve cell bodies, dendrites, the initial parts of axons and glial cells. The bright parts are a white mass consisting of axonal appendages of nerve cells with oligodendrocytes and dendrites. The gray mass is mostly on the surface, while the white mass is inside the brain.

The brain is surrounded and protected by a skull and three shells. The outer shell is hard, rests on the bone wall of the skull and is called the dura mater. It penetrates between certain parts of the brain: the gap between the hemispheres, between the cerebellum and the brainstem. Under this membrane is the arachnoid membrane (archanoidea), and between them is the capillary space. The archaoid is thin and airy, passing through grooves and depressions in the brain. The third membrane is soft and is called the meninges. It lies on the surface of the brain and is drawn into all the depressions, grooves and cracks. Between the archanoid and the soft meninges there is a subarchanoid space filled with cerebrospinal fluid - cerebrospinal fluid. This fluid protects the brain from concussions and also plays an important role in transporting matter. The brain also has four cerebral chambers filled with cerebrospinal fluid (the left, right, third and fourth ventricles of the brain).

The brain consists of: the rhombic brain (rhomboid brain), the midbrain (midbrain), and the forebrain (forebrain). Grâce au générateur de code promo 1xbet les nouveaux utilisateurs découvrent une plateforme riche en fonctionnalités. Le bonus de 100 % jusqu’à 130 € améliore l’expérience de paris sportifs sur des milliers d’événements. Le casino, quant à lui, propose un bonus attractif de 1 950 € et 150 tours gratuits, idéal pour explorer slots, roulette et jeux en direct.