Nervous System Flashcards
what kinds of messages does the nervous system send?
electrical messages
list the 5 functions of the nervous system
- maintain homeostasis
- receive sensory input
- integrating information
- controlling muscles and glands
- establishing and maintaining mental activity
list and describe the functions of the 2 cell types of the nervous system
- neuron: transmit signals
2. provide support for neurons
describe the general neuron structure
cell body and processes coming off the body
what does the cell body of a neuron contain?
the nucleus
describe the function of dendrites in a neuron
processes that conduct impulses toward the cell body, receive signals from another cell
describe the function of Axons in a neuron
processes that conduct impulses Away from cell body to the next cell
describe the myelin sheath of a neuron
a lipid substance which covers most axons and serves as an electrical insulator
describe the Nodes of Ranvier in a neuron
spaces between myelin, electrical signal jumps from node to node so it moves quicker
what are axons sometimes also called?
neuron fibers or nerve fibers
what does the central nervous system contain?
the brain and spinal cord
what does the peripheral nervous system contain?
components outside of the brain and spinal cord
what is referred to as a nucleus in the central nervous system?
a group of neuron cell bodies
what is referred to as a tract in the central nervous system?
a bundle of axons or neuron fibers
what is referred to as a ganglion in the peripheral nervous system?
a group of neuron cell bodies
what is referred to as a nerve in the peripheral nervous system?
a bundle of axons or neuron fibers
what do synapses do in the nervous system?
provide continuity from one neuron to the next
what is the relation between axons and dendrites during signalling?
the axon of a neuron meets the dendrite of the next but they do not touch!
since the axon of one neuron does not touch the dendrite of the next during signalling, what is the space between them called?
synaptic space
what do axons release into the synaptic space during signalling?
neurotransmitters
what do neurotransmitters do?
bind to receptors on the dendrite during signalling
how does the signal always travel during signalling?
from axon to dendrite
how many more neuroglia are there than neurons?
neuroglia outnumber neurons 10 to 1
list the 4 types of neuroglial cells
- olidodendrocytes (CNS)/Schwann cells (PNS)
- astrocytes
- ependymal cells
- microglia
