Ch 3: Anotmoy Of Nervous System Flashcards
Central nervous system
Brain, spinal cord
Peripheral nervous system
Located outside skull and spine
Brings info into and out of CNS
Somatic and autonomic
Somatic NS
Carry sensory Info to CNS from skin and musculature and contains motor fibers
Afferent neurons: Arrive- sensory info to CNS
Efferent neurons: Exit- sensory info out to muscle and glands
Autonomic
Involuntary PNS
Sympathetic and parasympathetic
Sympathetic
Fight or flight: prepares body to cope with emergency stress or arousing situation
Parasympathetic
Rest and restore
Conserve energy and promote vegetative functions of body
CNS structure
Encased in bone and covered by 3 meninges
Dura mater
Tough outer layer of CNS meninges
Arachnoid membrane
Web like( second layer in CNS meninges)
Pia mater
Adheres to CNS surface (thin translucent)
Cerebrospinal fluid
Fluid serves as cushion in CNS
Cerebral ventricles
Fluid filled caverns and canals inside brain
CSF (cerebral spinal fluid) advantages
- Buoyancy: reduces momentum and acceleration of brain when displaced
- Garbage collector: removes waste products from neuronal meta.
Hydrocephalus (water head)
Flow of CSF from ventricular system to the subarachnoid. space impaired causing swelling of ventricles
Blood brain barrier
Arrangements of endothelial cells: (tightly joins to one another) that form walls of capillaries
Needed because mature brain doesn’t replace most neurons.
Functions of B. B. B.
- Protects brain from foreign substances in blood that may injure brain
- Protects brain from hormones and neurotransmitters in rest of body
- Maintains constant environment
Neurons
Specialized cells for the reception conduction and transmission of electrochemical signals
Cell membrane
Lipid bilayer with signal proteins and channel proteins embedded in it
Solutions to discovering cells that make up brain
- Compound microscope
- mircotome: ability to fix tissue and make thin slices
- nissl stain: development of stains, color some but not all parts
Nissl staining important aspects
- Distinguishes neurons and glia from one another
2. Study Cytoarchitecture in diff brain areas
Golgi stain
Highlighted a small number of neurons in entirely
- Swalen central region
- Thin tubes that radiate from cell body called neurites (axons and dendrites)
Golgi’s view
Neurites of cells fused together to form network = reticular
Cajal’s view
Neurites not continuous but do come in contact. Communicate by contact = neuron doctrine
Gilal cells
Forgotten cells, support neurons, outnumber neurons, gilal communication and modulatory
Oliogodendrocities
Gilal class
Rich in myelin create myelin sheath
Schwann cells
Gilal class
Similar to myelin but in PNS, guide axonal regeneration
Astrocytes
Gilal cells
Largest, star shaped, many functions
Microglia
Gilal class
Response to injury or disease
Horizontal plane
A slice parallel to the ground
Frontal plane
Slicing bread/ salami
Saggital plane
Seperates left and right halves
5 major divisions of brain
Telencephalon, diencephalon, mesencephalon, metencepahlon, mylenceohalon
Hindbrain
Metencepahlon, mylenceohalon
Mylencephalon
Origin of reticular formation, largely of tracts
Medulla
Medulla oblongata: controls a number of reflexes( heart rate, breathing, vomiting, sneezing)
Metencepahlon
Many tracts
Pons-ventral surface
Cerebellum: sensorimotor coordination and balance may be more active in organizing sensory info that guides Movement
Pons: (bridge) many axons cross from one side of brain to to other. Nuclei for several cranial nerves
Mesencephalon (midbrain)
Textum: (roof) 2 swelling
- Superior colliculus: vesicles orienting
- Inferior colliculus: auditory
Tegmentum: periqueductal gray- pain
Substancia Nigra- motor movement
Ventral tegmental area- reward
Substancia Nigra
Parkinson’s disease- neurons are dying off ( dopamine degenerating )
To solve give levidopa: gets synthesized into dopamine
Forebrain
Diencephalon, telencephalon
Diencephalon
Thalamus: several different nuclei. Relay sensory into cerebral cortex
Hypothalamus: motivated behaviors, feeding, drinking, sex (below thalamus)
Telencephalon (cerebral cortex)
Serve to increase surface area
Corpus collosum: largest hemisphere- connecting tract
Longitudinal fissure: groove that separates right and left hemis.
Telencephalon subcortical structures
Limbic system: regulation of motivated behaviors (mammillary bodies, hippocampus, amaygdala, fornix, cingulate, septum)
Basal Ganglia: motor system (amaygdala, striatum, globus pallidus)
Damage to basal= Parkinson’s
Allows us to perform movements to obtain rewards
