The central nervous system
The central nervous system contains centers for receiving, analyzing, and ordering sensory information, and it consists of: the brain and the spinal cord, which are protected by many means; They are: the skin and hair that protect the skull, the skull bones that protect the brain, the vertebrae that protect the spinal cord, and the meninges that surround and protect them. In this article, we will shed light on the brain, and a simple explanation of its parts.
Parts of the brain
The brain consists of about a hundred billion multi-polar neurons, with a mass of about 1.4 kg, and the brain consists of the cerebrum, the diencephalon, the brain stem, and the cerebellum, and in what follows a simple explanation of each part.
The cerebrum is the largest part of the brain, and it contains the nerve centers related to sensory, motor, and higher mental functions. The brain is divided longitudinally into two cerebral hemispheres linked by a bridge of nerve fibers, and each of them is surrounded by the membranes of the meninges.
The brain is crossed. Where the right hemisphere controls the left part of the body, and the left hemisphere controls the right part of the body.
There are on the surface of the brain many folds called gyri, and separates the convolutions brain Othelam divide each cerebral hemisphere into lobes lobes know the names of the bones of the skull covered, called the outer layer of gray thin brain: cerebral cortex Cerebral Cortex , and contains nerve cells and short fiber bodies, divided The cerebral cortex is divided into three functional parts:
- Sensory centers: receive sensory information received from the senses.
- Motor centers: regulate voluntary movements of striated muscles.
- Organized centers: The centers of thinking, intelligence, creativity, memory, emotions, language, and the analysis and interpretation of sensory information, the white inner part is called the medulla, and it consists of long myelin nerve fibers.
The diencephalon consists of the left and right thalamus, each of which passes sensory information towards the brain, and they contain organized centers for sensory information, and the hypothalamus area responsible for maintaining the stability and balance of the internal environment of the body, and it contains centers for regulating hunger, thirst, sleep, body temperature, and balance Aqueous, which is the center of emotions and self-functions, and it controls the production and secretion of hormones by the pituitary gland, and cooperates with the medulla oblongata, and the medulla in regulating self-functions that regulate breathing, blood pressure, and heartbeat.
- The midbrain: in which it processes visual and auditory information, and controls reflexive actions related to them, such as moving the eyes, head, and neck towards a sudden sound source.
- Al Qantara - Al Jisr: It contains sensitive centers for oxygen concentration and pH in the blood, thus controlling the rate and depth of respiration.
- Medulla oblongata: It contains centers for regulating heart rate, respiration, smooth muscle contraction in blood vessels, and digestion, as well as centers for reflexes. Examples: coughing, sneezing, vomiting, and swallowing.
The cerebellum is the second largest part of the brain and plays a role in maintaining the balance of the body. It processes the information that comes to it from the senses, and recognizes from it the position of the body, and accordingly sends nerve impulses to the muscles, coordinating its work in order to maintain the balance of the body, after receiving information from the brain about what is the desired or desired position of the body parts, and sends it to the cord The spinal cord, which gives its orders to the skeletal muscles, contracting or relaxing to move the body to the desired position.