Nervous System Flashcards
General description of CNS and the PNS, be sure to include the structures/ organs in each as well as their general function
-CNS: consists of the brain and spinal cord
-PNS: consists of the nerves (bundles of axons) that connect the CNS to the other body parts
-Both systems provide 3 general functions:
sensory, integrative, and motor
What are the 2 divisions of PNS, be sure to include a brief description of each one
- Somatic: Voluntary, controls skeletal muscle
- Autonomic: Involuntary divides into 2 divisions motor and sensory
What is the role of Astrocyte
structural support join parts help regulate the concentrations of nutrients and ions
What is the role of Microglial Cell
Support neurons and phagocytize bacterial cells and cellular debris
what is the role of Ependymal Cell
Covers specialized brain parts (Choroid Plexuses) and form inner lining that encloses the brain
What is the role of Oligodendrocyte
Provide Insulating layers if myelin sheath around axons within the brain
What is the role of Schwann Cells
Produce myelin sheath around axons of myelinated neurons
Soma
Cell body nucleus and metabolic center of cell
Chromatophilic (nissl) Substance
Rough endoplasmic Reticulum
Dendrite
Conducts impulses towards the cell body
Neurofibrils
cytoskeleton filaments of main cell shape
Axon
Conduct impulses away from cell body
Axon Hillock
Cone- shaped thickening
What is the role of myelin
Myelin helps damage axons regenerate in the peripheral nerves
What is it material is myelin made of
Made of neurilemma
What are the neurolemma and Nodes of Ranvier
Neurolemma- Thin sheath around a nerve axon
Nodes of Ranvier- Narrow gaps between Schwann Cells
Difference between white matter and grey matter
White matter: group of myelinated axons
Grey matter: unmayelinated axons and neuron cell bodies
Function Classification of neurons
Sensory (afferent) neurons
- transmit info to the CNS
-Have specialized receptors ends usually unipolar some bipolar
Interneuron (Association) neuron
-found entirely in brain/spinal
-Transmit impulses from one part of the CNS to another
Motor (Efferent) Neurons
-Transmits impulses away from CNS to effector
-usually multipolar
Structural Classification of neurons
Multipolar Neurons
-have any processes arising from cell body
Bipolar Neurons
- have only 2 process one arise from each end of the cell body
Unipolar Neurons
- Single process extending from cell body