Anatomy - Nervous System Flashcards
Central Nervous System
Brain, spinal cord
Peripheral Nervous System
cranial nerves, spinal nerves, ganglia
General functions of CNS and PNS
Collecting information, processing and evaluating information, responding to iformation
Two types of nervous system cells
Neurons (nerve cells) and glial cells
Functions of neurons
electrically excitable and transmit and receive impulses
Functions of glial cells
Support and protection
What are some special characteristics of neurons?
High metabolic rate, extreme longevity and mostly non-mitotic, most cell bodies have one or more processes
What structures are part of the typical neuron?
Cell body, dendrites, axon, axon hillcock
Cell body of a neuron
biosynthetic centre
Dendrites
short processes that branch from the cell body and receive nerve impulses
Axons
transmit nerve impulses to other cells
Axon hillcock
connects to the cell body
Where do neuroglia exist?
CNS and PNS
Compare and contrast neurons and glial cells.
Glial cells are smaller, undergo mitosis and there are more of them. Additionally, glial cells protect and nourish while neurons are electrically excitable and transmit and receive impulses.
List four types of glial cells that are found in the CNS
astrocytes, ependymal cells, microglial cells, oligodendrocytes
What is an astrocyte?
blood vessel to neurons and form the blood brain barrier
What do ependymal cells do?
They produce CSF
What do microglial cells do?
They are part of the immune response
What do oligodendrocytes do?
generate myelin
What are the two major neuroglia of the PNS?
Satellite cells and Schwann cells
Describe a satellite cell
A glial cell found in the PNS that surrounds neuron cell bodies. They can be considered similar to astrocytes of the CNS.
Describe Schwann cells
A glial cell of the PNS that forms myelin sheaths around nerve fibers (insultation). They also help to regenerate fibers. They can be considered similar to the oligodendrocytes of the CNS.
List the three connective tissues of the nerve structure.
Endoneurium, perineurium, epineurium
What does the endoneurium surround?
Each axon
What does the perineurium surround?
Each individual fascicle
What does the epineurium surround?
around the entire nerve
What is the difference between the CNS and PNS?
CNS is brain and spinal cord. It processes and evaluates information to send to the effectors. PNS is the cranial nerves, spinal serves and ganglia. It acts as receptor of information to send to the CNS and acts as effectors for the response determined by the CNS.
What are the four major regions of the brain?
Cerebrum, diencephalon, brainstem and cerebellum
Describe the outer surface of the brain’s cerebrum.
It is wrinkled with gyri, which are folds, and suci, which are depressions between the folds.
Define gray matter in the CNS
Composed of cell bodies, dendrites, unmyelinated axons. It forms te brain cortex (brain surface) and forms clusters (cerebral nuclei).
Define white matter in the CNS
Myelinated axons. It is deep to the cortex.
What structures support and protect the brain?
The bony cranium, the protective connective tissue known as the meninges, the cerebrospinal fluid (CSF) and the blood brain barrier.