Human Regulatory System Consist of: 1. Neural System 2. Endocrine System 3. Sensoric Organ Neural System • Contains: nucleus, mitochondria, other organelles typical of eukaryotic cells • Grey colour receive information from another cell and transmit the message to the cell body Nerve cell body Neuron/Nerve Cell Dendrites ( 100 billion) Neural System Axon transmit nerve messages conducts messages away from the cell body. Cell Neuroglia/Glial Cell in direct contact with neurons and often surround them Nerve Cells and Astrocyte (SEM x2,250) Neural System Cross section of myelin sheaths that surround axons 3 kinds of neuron based their function •have a long dendrite and •have a long axon and short short axon •carry messages from sensory receptors to the central nervous system dendrites •transmit messages from the central nervous system to the muscles (or to glands) • found only in the central nervous system • they connect neuron to neuron Neural System kinds of neuron based their structure Neural System Sumsum tulang belakang (spinal cord/medula spinalis) Neural System Organization 12 pasang saraf otak (saraf kranial) Somatic sensory Saraf tepi Saraf simpatetik Saraf otonom (unvoluntary) Saraf parasimpatetik Saraf tak sadar (peripheral n.s) PNS 31 pasang saraf sumsum tulang belakang (saraf spinal) Saraf sadar Saraf pusat (central n.s) CNS Otak (brain) Otak besar/serebrum Otak tengah/mesencephalon Otak depan/prosencephalon Otak belakang/rhombencephalon Otak kecil/serebellum Sumsum lanjutan/medula oblongata Central Neural System Three basic functions are performed by nervous systems: 1. Receive sensory input from internal and external environments Sensory input can be in many forms, including pressure, taste, sound, light, blood pH, or hormone levels, that are converted to a signal and sent to the brain or spinal cord 2. Integrate the input and output The response, a motor output, is a signal transmitted to organs than can convert the signal into some form of action, such as movement, changes in heart rate, release of hormones, etc 3. Respond to stimuli Central Neural System Impulse is stimuli that receive by receptor and than bring by neuron. Commonly in electrical charge form There are two mechanism of impulse conducting: 1. By neuron 2. By synapses Central Neural System 1. By neuron Caused by: unequal distribution of ions and electrical charges between the two sides of the membrane. The outside of the membrane has a positive charge (Sodium/Na), inside has a negative charge (potassium/K). Changed polarity of the membrane, the action potential, results in propagation of the nerve impulse along the membrane Steps in an Action Potential 1. At rest the outside of the membrane is more positive than the inside. 2. Sodium moves inside the cell causing an action potential, the influx of positive sodium ions makes the inside of the membrane more positive than the outside. 3. Potassium ions flow out of the cell, restoring the resting potential net charges. 4. Sodium ions are pumped out of the cell and potassium ions are pumped into the cell, restoring the original distribution of ions. Central Neural System 2. By synapses Synapses? The junction between a nerve cell and another cell Central Neural System How is the process? -Impulse arrives at synapses -vesicle move to the end of pra synapses membrane vesicle discharge neurotransmitter (acetylcholine) - Acetylcholine diffuse trough the synapse cleft -bind to the receptor of post synapses membrane -cause impulse on next axon. Acetylcholine degrade by Acetylcholineterase that produced by post synapses membrane Central Neural System Ordinary movement stimuli receptor sensory nerve CNS (brain) motor nerve effector (muscle) response Reflex movement stimuli receptor sensory nerve spinal cord (connector) motor nerve effector (muscle) response Central Neural System (Brain) Brain save in skull bone, covered by meninges membrane. Meninges composed by 3 layers: 1. duramater: outer, stick in bone 2.arachnoid: between dura and pia Subarachnoid: between arachnoid and pia consist of ventricle that contain cerebrospinal liquid cerebrospinal feeding brain save brain from quake 3. piamater: inner The functions of brain are: 1. Receive sensory stimuli from inside and outside the body 2. Processing and coordinating the excitatory response 3. Maintain unconscious motion 4. Controlling activities Central Neural System Brain Prosen cephalon cerebrum Hipotalamus Lobus oksipitalis Lobus parietalis Lobus temporalis Lobus frontalis Mesen cephalon Rhomben cephalon Kolikuli superior cerebellum Kolikuli inferior Medula oblongata Pons varolii Central Neural System Cerebrum cover by two layer. Those are: Korteks: outer, grey grisea that contain nerve cell, neuron ajustor center of most activities control Medula: inner, white alba contain nerve fiber Subarachnoid Central Neural System Central Neural System Central Neural System Neural System Central Neural System Spinal cord/medula spinalis Spinal cord Ganglion motor nerve cell bodies Spinal segments: Sensory nerve cell bodies Central Neural System Spinal cord/medula spinalis: Outer (tracts). white matter, made up of bundles of inter neuronal axons 1. dorsalis sensoric/ascending tract(carrying messages to the brain) 2. ventralis motoric/descending tract (carrying messages from the brain) 3.Spinal nerve (sensoric and motoric) Inner gray matter (H formation/butterfly wings), consists mostly of cell bodies, synapses, connector cell without myelin, and dendrites. Central tract consist of cerebrospinal The spinal cord is also involved in reflexes that do not immediately involve the brain. Peripheral Neural System Based on their impulse pathways: • • sensory (afferent) pathways that provide input from the body into the CNS. motor (efferent) pathways that carry signals to muscles and glands (effectors). Based on their activities manner: • Somatic PNS: Cranial n.s composed by brain nerve fiber (12 pairs) Spinal n.s composed by spinal cord nerve system (31 pairs) • Otonom PNS: sympathetic increase organ activities parasympathetic: decrease organ activities Peripheral Neural System Peripheral Neural System Neural System Disorders Some neurotransmitters are excitory, such as acetylcholine, norepinephrine, serotonin, and dopamine. Some are associated with relaxation, such as dopamine and serotonin. Dopamine release seems related to sensations of pleasure. Endorphins are natural opioids that produce elation and reduction of pain, as do artificial chemicals such as opium and heroin. Neurological diseases, for example Parkinson's disease and Huntington's disease, are due to imbalances of neurotransmitters. Parkinson's is due to a dopamine deficiency. Huntington's disease is thought to be cause by malfunctioning of an inhibitory neurotransmitter. Alzheimer's disease is associated with protein plaques in the brain. Neural System Disorders Drugs are stimulants or depressants that block or enhance certain neurotransmitters. Marijuana, material from the Indian hemp plant (Cannabis sativa), has a potent chemical THC (tetrahydracannibinol) that in low, concentrations causes a euphoric high (if inhaled, the most common form of action is smoke inhalation). High dosages may cause severe effects such as hallucinations, anxiety, depression, and psychotic symptoms. Neural System Disorders Cocaine is derives from the plant Erthoxylon coca. Inhaled, smoked or injected. Cocaine users report a "rush" of euphoria following use. Following the rush is a short (5-30 minute) period of arousal followed by a depression. Repeated cycle of use terminate in a "crash" when the cocaine is gone. Prolonged used causes production of less dopamine, causing the user to need more of the drug. Neural System Disorders Heroin is a derivative of morphine, which in turn is obtained from opium, the milky secretions obtained from the opium poppy, Papaver somniferum. Heroin is usually injected intravenously, although snorting and smoking serve as alternative delivery methods. Heroin binds to ophioid receptors in the brain, where the natural chemical endorphins are involved in the cessation pain. Heroin is physically addictive, and prolonged use causes less endorphin production. Once this happens, the euphoria is no longer felt, only dependence and delay of withdrawal symptoms.
