Oscar Quiroz
Period 5
Nervous system
Major divisions and subdivisions of the nervous system
Tissues
Classification of neurons
Major functions of the nervous system
Action potential and nerve impulse
Connective tissue coverings
Major parts and functions of the brain
Cranial nerves
major functions and parts of the spinal cord
The tissues of the nervous system are the neurons and the neuroglia. The nervous tissue consists of two principle cell types and they are glial cells with small cells that surround and wrap delicate neurons and the nerve cells are the excitable cells that transmits electrical signals.The four main neuroglia support CNS neurons and the functions include is that it support and brace neurons and there are microglial cells and they are small oviod cells with thorny processes that touch and monitor neurons.Ependymal cells that range in shape.The oligodendrocytes, the branched cells.
The major functions and parts of the spinal cord are that it begins in the vertebral column that begins at the foreman and ends at L1 or maybe L2. The functions of the spinal cord is that it provides a two-way communication to and from the spinal cord and it has a major reflex center which means that reflexes are initiated and completed at the spinal cord.Another part to the spinal cord is epidural space and it's function is that it's a cushion of fat network of veins in space between vertebrae and spinal dura matter.Additionally to the spinal cord is the
The major and subdivisions of the nervous system is that the nervous system is divided into two parts and they are the central nervous system which controls the brain and spinal cord of the dorsal body cavity, and the peripheral nervous system which is the portion of the nervous system outside of the CNS. The PNS has two functional divisions which is the sensory(afferent) division and it has somatic sensory fibers that convey impulses from skin, skeletal muscle and joints to CNS, visceral sensory fibers that conveys impulses from visceral organs to CNS. The other division is the motor(efferent) vision that transmits from CNS to effector organs.
The major parts of the brain are the lobes and they're frontal, parietal, occipital. The front part of the brain is the cerebrum and the back part is the cerebellum. The longitudinal fissure is a long line in the center of the brain that separates the hemisphere and the transverse fissure is a horizontal line in the lower part of the brain is what separates the cerebrum and cerebellum. The left hemisphere of the brain is what controls language,math and logic and the right is the visual-spatial skills, and emotion. The cerebellum consists of 11% brain mass, cerebellar hemispheres connected by worm like vermin and the functions of the cerebellum is that it balances and coordinates and plays role in thinking, language and emotion
Neurons also called nerve cells, they are structural units of the nervous system also they are large, highly specialized cells to conduct impulses.The neuron cell body, also known as perikaryon or soma, it contains nucleus with nucleuclus along containing some pigaments. The Nuclei are clusters of neuron cell bodies in CNS and Ganglia are clusters of neuron bodies in the PNS. The neuron processes are tracts which are bundles of neuron in the CNS, the nerves are neurons processes in PNS and the two types of processes are dendrites and axons.
A connective tissue covering is the dura matter, a white stretchy that covers the entire nervous system and protects the brain from impacts Another connective tissue covering is white matter which runs in three directions and that is ascending, descending, and transverse and the white matter is divided into three white columns which was lateral, ventral conterior, and dorsal (posterior) and it is myelinated and nonmyelinated axons.The gray matter is short, nonmyelinated neurons and cell bodies
The major functions of the nervous system is that it is the master of controlling and communicating the body.It also has three overlapping functions and they are the sensory input which is when information is gathered by sensory receptors, the intergration is processing and interpretation of sensory input and the motor output is the activation of effector organs.
The action and nerve impulse of the nervous system is the preception of the pain, meaning that some of pain impulses are blocked by inibitory endogenous opiods, the pain tolerance is when genes help determine pain tolerance as well as responce to pain medications and referred pain and means pain from one body region perceived as coming from different regions.
Spinal nerves
The spinal nerves are part of the PNS and it is attached to the spinal by 31 paired roots and the Caudal equine is the collection of nerve roots in the interior end of the vertebral canal.The two length wise grooves that run the spinal cord is the ventral, which is the "median fissure" and the dorsal is the "median suleus". They are also formed by fusion of dorsal and ventral roots.
Neurotransmitters
There are 12 cranial nerves that are associated with the brain.
1:Olfactory nerves-sensory nerves to smell
2:Optic nerves-Purely sensory (visual) function
3:Oculomotor nerves-lens shape, directing eyeball and constricting
4:Trochlear nerves-Primarily motor nerve that directs eyeball
5:Trigeminal nerves-Supply motor fibers for mastication
6" Abducens nerves-Primarily a motor that innervates lateral rectus muscles
7.Facial nerves- Sensory function (taste) from anterior two-thirds of tongue
8:Vestibulocochlear nerves- Formerly auditory nerve
9:Glossopharyngeal nerves- Fibers from medulla leave skull via jugular foreman and runs to throat
10.Vagus nerves- Fibers from medulla exit via jugular foreman
11:Accessory nerves- Formerly spinal accessory nerve
12:Hypoglossal nerves- Fibers from medulla exit skull via hypoglossal canal
The neurotransmitter is the language of the nervous system and there are 50 or more transmitters that have been identified.
Reflex arc
Reflexes are rapid, automatic, and respond to the stimuli.The arcs of reflex are receptors that is the site of stimulus action , sensory system that transmits afferent impuluses to the CNS, integration center that is either mono synaptic or postsynaptic region , motor neurons which conducts efferent impulses from integration center to effector organs and the effectors is the muscle fiber or gland cell that resonds to efferent impuuses by contracting or secreting.
Disorders/diseases
A disorder/disease in the CNS(central nervous system) is meningitis which is inflammation of the meninges and that can spread to the CNS.A brain injury is severe when you get a concussion and a alteration in function and a contusion is when permanent damage.If you get in a cerebrovascular accidents you could get a stroke such as ischemia which is when the tissue is deprived of blood supply and hemiplegia is paralysis on one side of the body.A disease is Alzheimer's disease that can cause memory loss, Parkinson disease is degeneration of the dopamine released neurons and Huntington's disease is what causes jerky "flapping" movements.
Drugs of abuse
The drugs that affect the human body is methamphetamine which removes dopamine from the synaptic cleft and the persons mood changes by making the user feel intense pleasure.Alcohol affects the brain by delivering a seditive punch and it interacts with GABA receptors and it affects the area involves the memory formation.Cocaine affects the brain by blocking the transporters that leave the dopamine in the synaptic cleft and it abuses are fidgety and unable to be still.The LSD affects the brain that might inhibits the and excite the transmitters and it affects the persons mood by branching a single neuron which is responsible for feelings.
Another part of the brain is the medulla oblongata, that is also known as medulla,contains the fourth ventricle and the functions of it is the cardiovascular center which adjusts force and rate of the heart contraction and the respiratory center is that it generates respiratory along with vomiting and coughing.
Other set of disorders for the spinal cord is parenthesis which is caused by damage-sensory function loss, another is paralysis that is caused by damaged to the ventral roots or ventral horn cells but there are two types of paralysis and they are paraplegia which is when there is transection between T1 and L1 and quadriplegia which is transection in the cervical region.
The heroine affects the brain is that it mimics natural opiates and binds to receptors and it affects the mood of someone by being responsible for pain signals, stress response.ecstasy affects the brain by confusing the transporters then starts transporting serotonin out of the cell and affects the persons mood by affecting the serotonin that is responsible for sleep, mood and appetite. The marijuana affects the brain by mimicking the anadomide and binds to canabinoid receptors and it affects the person's mood by removing unnecessary short term memory.
Endoneunium is loose CT that encloses axons and myelin sheaths, The perineurium is the coarse CT that hundles fiber into facides, and the epineurium and tough fibrous sheath around all fascides to form nerves.