Human Nervous System Level3By Graciela Garcia
Functions of the Nervous System: Brain detects changes in the environment externally
and internally Brain stores information Brain responds by starting changes in the nerves
and glands Maintains homeostasis Brain processes signals
The cross section layers of the brain:• Longitudinal
Tissue-Separates brain medially • Lateral Tissue-Separates temporal and frontal lobes.
• Central Sulcus-Separates frontal and parietal lobes
Divisions of the Nervous System:
Central Nervous System-Brain-Spinal Cord
Peripheral Nervous System
• Autonomic-Controls are involuntary-Blood flow, digestion, and heart Beat
• Somatic (not automatic)
-Chewing, walking, and running
The four lobes
Description of the four lobes of the brain: Frontal Lobe • Reasoning• Planning• Problem Solving• Thinking
Parietal Lobe • Recognizing • Stimuli orientation• Speech
Temporal Lobe• Memory• Speech • Auditory stimuli
Occipital Lobe• Visual Processing • Hallucinations
Spinal Nerves: Sacral
TailboneSpinal nerves: 5-Innervate posterior legs and buttocks ThoracicChestSpinal Nerves: 12-Innervate trunk and parts of arms
CervicalNeckSpinal nerves: 8-Innervate back of head, upper back, and neck
Lumbar Lower backSpinal nerves: 5-Innervate lower abdomen and anterior legs
Diagram
Cranial Nerves:-Olfactory: the sense of smell
-Optic: does the vision -Abducent: abduction of the eye
-Facial: Facial expressions, saliva, tears, and taste
The Neuron & it’s Parts: A neuron is a nerve cell that forms chains that go through-out
your whole body including the brainPARTS OF A NEURON:
Dendrite (receives transmitters from environment) Cell Body (contains nucleus, and is largest part of cell) Nucleus (in cell body and contains DNA) Axon (tube that sends signals from cell body to axon terminal) Myelin Sheath (lipid [fat] that keeps chemicals inside axon to
speed up transmission of the signal) Axon Terminal (end of axon where neurotransmitters are released) Neurotransmitters: chemical released into synaptic elect and to
attach themselves to receptors on next neuron) Synaptic Cleft: gap between neurons)
Neuron
Flow of the CSF:• Cerebrospinal Fluid – Clear fluid that is made in the
spaces of the brain and circulates around the brain and spinal cord to cushion the brain and gives it nutrients.
-Some made in choroid plexus of lateral ventricle in brain-Travels through interventricular forearm to 3rd ventricle-Travels through 4th ventricle through cerebral aqueduct
Some travels to surround whole brain Some travel to spinal cord
• Absorbed by the arachnoid villi and filtered with the blood
The flow of CSF
Meninges:• Skin of scalp
Greater density of hair follicles
• Periosteum Connective tissue
layer
Bone Duramater Arachnoid Piamater