Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
HA Ch. 12 (13)
Nervous System I: Nervous Tissue
| Question | Answer |
|---|---|
| the nervous system is one of the ... yet... organ systems in the human body | smallest...complex |
| nervous system includes all of the | neural tissue in the body |
| the nervous system along with the ... controls and adjusts the activities of ... | endocrine...the other organ systems in the body |
| chief functions of nervous system | monitor, integrate, respond to information in the environment |
| CNS contains the | brain and spinal cord |
| PNS contains | nerves and ganglia |
| ganglia are all the nervous tissue structures external to the | CNS |
| the nervous system receives..and dictates | sensory inputs...motor outputs |
| 2 functional divisions of the nervous system | afferent and efferent |
| afferent = | sensory |
| afferent division carries...from...through the | sensory impulses...sensory receptors...PNS TOWARDS the CNS |
| efferent division = | motor |
| efferent division carries...through...to the... | motor impulses AWAY FROM the CNS...the PNS...effectors |
| effectors are | muscles and glands |
| efferent is further divided into the | somatic nervous system (SNS) and autonomic nervous system (ANS) |
| SNS provides | voluntary control over skeletal muscle contraction |
| ANS provides | automatic control involving regulation of smooth muscles, cardiac muscle, and glandular activity |
| types of sensory inputs and motor outputs are categorized as | somatic, visceral, general, special, branchial, proprioception |
| somatic refers to the | outer body |
| visceral refers to mainly the | inner body |
| general | widespread |
| special | localized |
| branchial innervation refers to | the motor innervation of pharyngeal muscle |
| proprioception refers to a series of senses that monitor the degree of | strech in muscles, tendons, and joint capsules |
| proprioception, therefor, refers to | sensing the positions and movements of the body parts |
| nervous tissue organization is comprised of | neurons and supporting cells called neuroglia or glial cells |
| neurons are | long-lived, non-dividing cells |
| each neuron has a | cell body (soma) and cell processes (axons and dendrites) |
| neuron cell SOMA contains a | nucleus surrounded by cytoplasm (nucleoplasm or perikaryon) |
| cytoplasm of neuron contains | supportive neurofibrils, neurotubules, neurofilaments and chromatophilic (Nissl) bodies |
| Nissl bodies are concentrations of | RER and free ribosomes |
| all neuron bodies are in the CNS except | for those found in ganglia of the PNS |
| axon hillock is the specialized region of an axon which connects | the initial segment of the axon to the cell body |
| axoplasm | cytoplasm of axon which contains numerous organelles |
| collaterals | side branches from an axon |
| terminal arborizations are a series of fine, | terminal extensions which branch from the tip of the axon and end at the synaptic terminals |
| terminal bouton is the area where | one neuron synapses on another |
| axolemma | plasmalemma of an axon |
| ganglia (PNS) | clusters of PNS neuron cell bodies |
| nerves (PNS) | bundles of axons in PNS |
| most neurons have a # of branched | dendrites which are receptive sites that conduct signals from other neurons TOWARD the neuron cell body |
| most neurons have one | axon which generates and conducts nerve impulses AWAY from the neuron cell body |
| synapse is a functional | junction between neurons at neuroeffector junctions |
| synapses function as a | site of intercellular communication |
| synapses occur on | dendrites, the cell body, or along axons (axodendritic, axosomatic, axoaxonic) |
| vesicular synapse = | chemical synapse involving neurotransmitters |
| nonvesicular synapse = | electrical synapse involving direct contract between cells |
| anatomically, neurons are classified by the | number of processes issuing from their cell bodies (multi, bi, uni, pseudouni, anaxonic)(polar) |
| multipolar | several dendrites and one axon |
| bipolar | one dendrite and one axon |
| unipolar | one process |
| pseudounipolar | the dendrite and axon are continuous at one side of the cell body |
| anaxonic | contains no distinguishable axon |
| functionally, neruons are classified according to the | direction in which they conduct impulses (sensory, motor, interneruons) |
| sensory (afferent) neurons conduct impulses | TOWARDS the CNS |
| motor (efferent) neurons conduct impulses | AWAY from the CNS |
| interneurons (association neurons)lie in the | CNS between sensory and motor neurons |
| there are non-neural supporting cells in the neural tissue which | support, protect, nourish and insulate neurons |
| supporting cells of the nervous system | neuroglia or glial cells |
| neuroglia of the CNS include | astrocytes, microglia, ependymal, oligodendrocytes |
| astrocytes are the | largest andmost numerous of the glial cells |
| astrocytes function in controlling the | interstitial environment |
| astrocytes repair | damaged neural tissue |
| astrocytes create a | 3-D framework for the CNS |
| astrocytes guide | neuron development |
| astrocytes maintain the | blood-brain barrier which isolates the CNS from the environment |
| microglia | phagocytic cells of the CNS |
| microglia cells engulf | cellular debris, waste products and pathogens |
| ependymal cells | cuboidal to columnar epithelial cells that line the central canal and ventricles of the brain |
| oligodendrocytes | glial cells responsible for maintaining cellular organization in the gray matter and producting myelin to completely sheath areas of white matter |
| neuroglia or supporting cells of the PNS include | schwann cells and satellite cells |
| schwann cells | myelin forming cells that cover all peripheral axons, whether myelinated or unmyelinated |
| satellite cells | enclose neuron cell bodies in the peripheral ganglia |
| satellite cells regulate the | exchange of nutrients and waste products between the neuron cell body and the extracellular fluid |
| thick axons are | myelinated |
| myelin speeds | impulse conduction along axons |
| myelin sheath = a coat of | supporting cell membranes wrapped in layers around the axon |
| the myelin sheath has gaps called | nodes of ranvier |
| unmyelinated axons are surrounded by | supporting cells but they are not wrapped by layers of myelin |
| a peripheral nerve (simply nerve) is a | bundle of axons wrapped in CT in the PNS |
| each axon is enclosed by an | endoneurium |
| each fascicle of axons is wrapped by a | perineurium |
| the whole nerve is surrounded by the | epineurium |
| nerves are | organs because they contain more than one kind of tissue |
| reflexes are | rapid, automatic responses to stimuli |
| reflexes can either be | somatic or visceral |
| 5 minimum number of elements in a reflext | receptor, sensory neuron, integration center, motor neuron, effector |
| simple 3 neuron reflex arcs form the basis of the | structural plan of the entire nervous system |
| sensory neurons enter the | spinal cord dorsally |
| motor axons exit | it ventrally |
| interneurons are the | confined to the CNS |
| the nerves in the PNS consist of the peripheral axons of the | sensory and motor neruson |
| cell bodies of motor neurons and interneurons make up the | internal gray matter of the CNS, whereas the cell bodies of sensory neurons lie external to the CNS in sensory ganglia of the PNS |
| throughout most of the CNS the inner gray matter is surrounded by | outer white matter |
| the extreme center of the spinal cord and brain is a | fluid-filled hollow central cavity |
Created by:
handrzej
Popular Anatomy sets