Topic 5 Flashcards
The nervous system maintains internal order within the body by coordinating the activities of muscles and organs. Comprising the central nervous system (CNS) and the peripheral nervous system (PNS), the mamalian nervous system receives input from sense organs which in turn generates output in the form of various responses and reactions within the body.
What are basic functions of the nervous system?
To sense changes (sensory), to interpret these changes (integrative), and to react to changes (motor)
Name the three distinct portions of the neuron.`
Cell body, dendites and axon.
What is axon covered with and what is their purpose?
Covered in myelin sheath. This increase the speed of impulses and to insulate and maintain the axon.
There are six types if nuroglial cells. What are these types of glial cells?
Astrocytes Oligodendrocytes Microglia Ependymal cells Schwann cells Satellite cells.
What is Nodes of Ranvier?
Gaps in the myelin. They are important for signal conduction.
What is white and grey matter?
White matter is axons that are myelinated.
Grey matter is cell bodies, dendrites, unmyelinated axons, axon termicals, neuroglia.
The brain cortex is made up of what matters?
Grey and white.
What is a resting membrane pontential?
It is when the membreane of a non conducting neuron is posively charged outside and negatively inside.
When does the inside of the neuron become positively charged?
When a threshold stimulus is presented.
What is the refractory period?
It is a short break when action potential has occured
Do larger nerve fibres conduct impulses faster?
Yes
Saltatory conduction only occurs in the presence of what?
Nodes of Ranvier
What is the junction between neurons called?
Synapse
How are neurotransmitters removed?
Diffusion, enzymatic degradation, re-uptake
What are the major areas of the brain?
Medulla Cerebrum Diencephalon Cerebellum Midbrain Pons Medulla