Nervous system 12.1

The nervous system includes brain and spinal cord.

https://www.researchgate.net/figure/Organization-of-human-nerve-system_fig5_221719508

• Central Nervous Systems

• Peripheral Nervous Systems

• Nervous tissue, present in both the CNS and PNS.
• Neurons are cells and therefore have a soma.

• White matter is white because axons are insulated by a lipid-rich substance called myelin.
• Neuron cell bodies in the CNS is referred to as a nucleus.
•  In the PNS, a cluster of neuron cell bodies is referred to as a ganglion.
• A bundle of axons, or fibers, found in the CNS is called a tract whereas the same thing in the PNS would be called a nerve. 
• Attributed to different regions of the brain (such as the cerebral cortex or the hypothalamus)
• the optic nerve carries signals from the retina that are either used for the conscious perception of visual stimuli, which takes place in the cerebral cortex,
• First, the basic functions of the nervous system are sensation, integration, and response. 
• The nervous system not involving the brain or spinal cord is called  Peripheral Nervous System (PNS)
• Myelin sheath-White matter is found on the inside of the brain and the outside of the spinal cord. It is made up of this part of the neuron.
• Spinal cord-Forms part of the Central Nervous System along with the brain.
• Brain -Forms part of the Central Nervous System along with the spinal cord.
• Cerebrum-Largest part of the brain involved in information processing. Forms the connections between different parts of the brain (mostly white matter)
• Cerebellum-Part of brain responsible for balance and coordination
• Corpus callosum-Connects the left and right hemispheres of the brain
• Nervous system responses are FAST or SLOW
• Thalamus collects information from the body and sends it to the relevant part of the brain Post office'
• Dendrite are Part of a neuron that receives signals from other neurons or receptors.
• Cell body-Part of a neuron responsible for normal cell function.
• Axon terminal-The end of a neuron from where the signal changes from an electrical impulse into a chemical signal before it crosses the synapse.
• Neurotransmitter-The chemical which is released from an axon terminal and travels across a synapse to the next neuron.
• Stimulus-Causes a receptor to send a signal to a neuron
• Chemoreceptors -Receptors that detect chemicals eg. taste, smell.
• Mechanoreceptors-Receptors that detect movement eg. touch, hearing.
• Photoreceptors-Receptors that detect light eg. eyes
• Effector-The muscle or gland in which a response occurs due to stimulation of a motor neuron.
• Reflex-A fast and automatic response to immediate danger!
• Frontal lobe-Part of brain responsible for risk taking, emotions, and decision making. Underdeveloped in teenagers.
• Temporal Lobe-sitting close to ear level within the skull it is associated with processing auditory information and with the encoding of memory.
• Parietal Lobe-roughly located at the upper back area in the skull, it processes sensory information it receives from the outside world, mainly relating to touch, taste, and temperature.
• Occipital Lobe-Responsible for vision.
• Autonomic-The set of motor nerves that automatically control the operation of vital glands and organs; also called the involuntary nervous system( autonomic nervous system)
• Receptor-A sensory cell which receives information from the environment and passes it to the dendrite of a neuron.
• https://quizlet.com/591935885/nervous-system-flash-cards/