Flashcards in The Nervous System Deck (55)
What tissue controls and integrates all body activities, within limit, that maintain life?
What are the 3 basic functions of nervous tissue?
- sensing change
- interpreting ans remembering change
- reacting to change
What are the 2 general functions of the nervous tissue?
communicating and control
What are the 6 major structures in the nervous system?
- cranial nerves
- spinal cord
- spinal nerves
- enteric plexus
- sensory receptors
What is an enteric plexis?
a bundle of nerves that control GI function; brain doesn't control
What does the central nervous system include?
Brain and spinal cord
What does the peripheral nervous system include?
cranial and spinal nerves
What are the 2 main nerves in the PNS?
Motor nerves (sends message from CNS to muscles, or glands)
Sensory nerves ( send messages from sensory receptors to CNS
What are the 3 functional divisions of the PNS?
- somatic (voluntary)
- autonomic (involuntary)
- enteric (ENS independant)
In the somatic nervous system sensory neurons and special sense receptors send messages to _______.
In the somatic nervous system motor neurons receive messages from CNS to _______ muscle.
In the autonomic nervous system sensory receptors from ____ ____ send messages to CNS.
What are the 2 divisions of the ANS (autonomic nervous system)?
What is the sympathetic division of the ANS?
controls fight or flight response (energy)
What is the parasympathetic division of the ANS?
controls resting and digesting (relaxation)
What does the enteric nervous system do?
- the enteric nervous system is a network of sensory and motor neurons in the GI tract
- functions independantly
- controls GI function
Nervous tissue is composed of 2 different types of cells, name them.
- neurons (nerve cells)
- neuroglial cells
What is a neuron?
an individual nerve cell that i sthe functional unit of the nervous system and is electrically excitable
What is another name for the nerve cell body?
What are some characteristics of the stoma?
- has a nucleus
- cytoplasm has usual organelles as well as;
a. Nissl bodies (clusters of rough ER)
b. neurofilaments (give shape and support)
c. microtubules (intracellular transport)
d. lipofiscin pigment granules ( not sure of role but they increase in amount as we age)
What are some characteristics of dendrites?
- usually short and highly branched
- specialized for contact with other neurons
- conducts impulses toward the cell body
- contain neurofibrils and nissl bodies
An action potential moves from _______ to the _______.
b. axon terminals
What are some characteristics of axons?
- long slender process arising from axon hillock
- contains mitochondria, microtubules, neurofibrils
- conducts impulses away from the cell body
- axon terminals (at the end) contain vesicles filled with neurotransmitters
What is an axon hillock?
narrowing of the cell body
What are the 3 functional classifications of neurons?
- sensory (afferent) neurons
- motor (efferent) neurons
- inter (association) neurons
What is an afferent neurons?
a sensory neurons that transmits sensory info from the skin, muscle, joints, sense organs, and viscera to the CNS;
What is an efferent neurons?
transmits motor nerve impulses from the CNS to the muscles and glands
What is an association neuron?
aka interneuron; CONNECTS neurons within the CNS (makes up 90% of neurons)
What is the most common type of neuron classification?
multipolar; has several dedrites and one axon (joe blow neuron)