Flashcards in Nervous Tissue Deck (31):
What structures make up the Central Nervous System?
Brain & spinal cord
What structures make up the Peripheral Nervous System?
Cranial nerves, spinal nerves, ganglia, sensory receptors, somatic nervous system, autonomic nervous system, enteric nervous system
The spinal cord connects to the brain via what opening in the skull?
Afferent neurons are involved in what nervous system function?
sensory function - send sensory signals to the brain
Efferent neurons are involved in what nervous system function?
Motor function - brain sends signal to these neurons to act
What are cells contacted by efferent neurons called?
Interneurons are involved in what function?
integrative function - spinal cord and brain level - signal relay
How many cranial nerves are there?
How many spinal nerves are there?
Describe what happens when the sympathetic nervous system is active
increased heart rate, blood vessels of digestive system vasoconstrict, pupils dilate, blood vessels to muscles vasodilate
Which part of the PNS is involuntary?
autonomic nervous system - breathing, heart beat
The autonomic nervous system consists of what two subdivisions?
sympathetic and parasympathetic
What is the function of enteric motor neurons?
govern contraction of the GI tract
List the general functions of neurons
sensing, thinking, remembering, controlling muscular activity, regulating glandular secretions
What is the function of neuroglia?
nourish, support and protect neurons
What are dendrites of a neuron?
the receiving (input) portion of the neuron
What is the function of a neuronal axon?
propagate impulses toward another neuron, muscle fiber or gland cell
What is the function of synpatic end bulbs?
store and release neurotransmitter
site of communication between two neurons or between a neuron and an effector cell
Describe the structure of multipolar neurons
one axon, many dendrites
What is the function of astrocytes?
form the blood/brain barrier
What is the function of oligodendroctyes?
form myelin in the CNS
What is the function of microglia?
Responsible for phagocytosis in the CNS
What is the function of ependymal cells?
Form cerebrospinal fluid
What is the function of Schwann cells?
Form myelin in the PNS
What is the function of satellite cells?
Repair peripheral neurons
What is the function of the myelin sheath on an axon?
Form segments of insulation to increase speed of nerve impulse conduction
What is the average resting membrane potential of a neuron?
Name the 4 types of ion channels
Ligand-gated channel, leakage channel, voltage-gated channel, mechanically gated channel
Describe the electrochemical gradient
An electrical difference and a concentration difference across a membrane