Tuesday 6 June 2017

THE ANATOMICAL PHYSIOLOGICAL NERVOUS SYSTEM



THE ANATOMICAL PHYSIOLOGICAL NERVOUS SYSTEM

NETWORK IS CONSIST OF:
A.    Neurons (nerve cells)
It is an anatomical and functional unit of the neural system

              

Parts of the neuron:
Ø  Cell body (cell nucleus is inside)
Ø   Dendrites: impulse to the cell body
Ø   Axon: delivers impulses out of the cell body
Classification of Neurons by Form:
1.      Unipolar neurons
There is a bifurcated bulge close to the cell body, one branch toward the periphery & another branch toward the CNS (spinal neuron neurons)

2.      Bipolar neurons
Has two bulges, 1 axon and 1 dendrite

3.      Multipolar neurons
There are several dendrites and 1 axes that can branch off a great deal
Most of the organelles of the neuron cells are found in the cell's cytoplasm

Neuron function: conducts nerve impulses throughout the body (somatic and visceral)
Neuron impulses are electric along the neurons and are chemical between neurons (synaptic cleft / cleft cleft)
Chemically synthesized neurons and stored in axon vesicles are called impulsive neurotransmitters
Examples of neurotransmitters: acetylcholine, norefineprin, dopamine, serotonin, gamma-aminobutyrate (GABA)
B.     Support cells (Neuroglia on CNS & Schwann cells in SST). There are 4 neuroglia
1.      Microglia: acts as phagocytes
2.      Ependima: role in the production of CSF
3.      Astrocytes: role of providing nutrition neurons and maintaining biolelectric potential
4.      Oligodendrocytes: produce mielin pd CNS which is a neuron sheath

C.    Mielin
1.      a white fat protein complex that covers the nerve bulge (neurons)
2.      Blocking the flow of Na & K ions across the neural membrane.
3.      The non-bermielin region is called the ranvier node
4.      Transmission of nerve impulses mingles faster than mismatched, due to impulse jumps from one other kenodic node (saltatoric conduction)

DIVISION OF NATURAL SYSTEMS IN ANATOMY:
A.    CNS (Central Nervous System)
B.     Nervous System Edges

The central nervous system (CNS) includes the brain (encephalon) and spinal cord (medulla spinalis). Both are very soft organs, with a very important function then need protection. In addition to the skull and vertebral segments, the brain is also protected by 3 layers of meninges membranes. When this membrane is infected, inflammation is called meningitis.

The three layers of the membrane meninges from the inside out are as follows:
1.      Durameter; Consists of two layers, the outermost one united with the skull as endostium, and another layer as a duramater that is easily released from the head bone. Among the bones of the head with the duramater is the epidural cavity.
2.      Arachnoidea mater; So called because it looks like a spider's web. Inside is a liquid called liquor cerebrospinalis; A kind of lymph fluid that fills the sidelines of the arachnoid membrane. The function of the arachnoideal membrane is as a cushion to protect the brain from the danger of mechanical damage.
3.      Piameter. The deepest layer that has the shape is adjusted to the surface folds of the brain.
The brain and spinal cord have 3 essential matter:
1.      the cell body that forms the gray matter part (grissea substance)
2.      the nerve fibers that form part of the white matter (alba substance)
3.      neuroglia cells, ie connective tissue located between the nerve cells in the central nervous system
Although the brain and spinal cord have the same material but the arrangement is different. In the brain, gray matter is located on the outside or the skin (cortex) and the white part is located in the middle. In the spinal cord of the middle part of the material is a gray-shaped butterfly, while the cortex is white matter.
Brain
The brain has five main parts: the cerebrum, the midbrain (mesensefalon), the cerebellum, the marrow (medulla oblongata), and the varol bridge.




A.    Big brain (cerebrum)
The big brain has a function in the regulation of all mental activity, which is related to intelligence (intelligence), memory (memory), awareness, and consideration.
The big brain is the source of all activities / movements conscious or in accordance with the will, although there are also some brain reflex movements. In the cortex of the large gray-colored brain there is the excitatory part of the stimulus (area sensor) located at the rear of the motor area that functions to regulate conscious movement or respond to stimulation. In addition there is an association area that connects the motor and sensory areas. This area plays a role in the learning process, storing memories, making inferences, and learning various languages. Around the two areas are the parts that regulate higher psychological activity. For example the front is the center of the process of thinking (ie remembering, analysis, speaking, creativity) and emotion. The vision center is on the back.

B.     Middle brain (mesensefalon)
The middle brain is located in front of the cerebellum and the varol bridge. In front of the midbrain there is the thalamus and pituitary gland that regulate the work of the endocrine glands. The top (dorsal) of the midbrain is the optic lobe that regulates the eye reflexes such as pupillary narrowing, and is also the center of hearing.

C.     Small brain (cerebellum)
Cerebellum has a major function in coordination of conscious, balance, and body position movement. If there is an adverse or harmful stimulus then a normal conscious movement is not possible.

D.    Continuous marrow (medulla oblongata)
The conjunctive marrow serves to deliver impulses that come from the spinal cord to the brain. The connector also affects bridges, physiological reflexes such as heart rate, blood pressure, volume and respiration rate, gastrointestinal motion, and gastrointestinal secretion.
In addition, the bone marrow also regulates other reflex movements such as sneezing, coughing, and flashing.

E.     Bridge varol (pons varoli)
The varol bridge contains nerve fibers connecting the left and right brain, also connecting the cerebellum and spinal cord.



Based on its location, the brain can be divided into five namely:
1.      Telensefalon (end brain) consists of:
§  à Hemisfer cerebri
§  cerebral cortex
§  limbic system (ward ganglia, hippocampus, amygdala)

2.      Diensefalon (inter brain) consists of:
§  Epitalamus
§  Thalamus
§  Subtalamus
§  Hypothalamus

3.      Mesensefalon (mid brain) consists of:
§  Superior Coliculus
§  Inferior Coliculus
§  Substansia nigra

4.      Metensefalon (after brain) consists of:
§  Pons
§  Serebelum
§  Mielencephalon
§  Medula oblongata

5.      Mielensefalon (marrow brain)

Spinal cord (spinal cord)
In the cross section of the spinal cord the outer part is white, while the inside is a butterfly and gray. In the cross section of the spinal cord there is a section like the wing split over the upper wing called the dorsal horn and the lower wing called the ventral horn. The sensory impulse of the receptor is transferred into the spinal cord via the dorsal horn and the motor impulse out of the spinal cord via the ventral horn to the effector. In the dorsal horn there is a connecting nerve cell body (association of connectors) that will receive an impulse from the sensory nerve cell and will deliver it to the motor nerve