Shared Flashcard Set

Details

Bio 210-Chapter 10
Nervous System
206
Biology
Undergraduate 1
11/05/2012

Additional Biology Flashcards

 


 

Cards

Term
What do the nervous system and endocrine system do that is similar?
Definition
function to regulate and coordinate all body activities
Term
What are the three functions of the nervous system?
Definition
sensory, integrative and motor
Term
Name the three types of neurons, give their function, and where each is located.
Definition
(1) sensory neuron transmits the impulse toward the CNS and is located in the PNS (2) interneurons transmits impulses within the CNS and are located in the CNS
Term
What are the two parts of the nervous system?
Definition
central nervous system (CNS) and peripheral nervous system (PNS)
Term
What does the CNS consist of?
Definition
brain and spinal cord
Term
What are the four parts of the brain?
Definition
cerebrum, cerebellum, diencephalon and brain stem
Term
What does the PNS consist of?
Definition
cranial nerves and spinal nerves
Term
What are the two subdivisions of the PNS?
Definition
somatic nervous system (SNS) and autonomic nervous system (ANS)
Term
Describe the actions of the SNS.
Definition
sensations are consciously perceived and the actions carried out are voluntary
Term
Describe the actions of the ANS.
Definition
sensations are not consciously perceived and the actions carried out are involuntary
Term
What are the receptors for the general senses?
Definition
touch, pressure, vibration, temperature, pain and proprioception
Term
What are the receptors for the special senses?
Definition
smell, taste, vision, hearing and equilibrium
Term
What are the effectors for the SNS?
Definition
skeletal muscle
Term
What are the effectors for the ANS?
Definition
cardiac muscle, smooth muscle and glands
Term
What are the two divisions of the ANS?
Definition
sympathetic division and parasympathetic division
Term
What are the two types of nerve cells?
Definition
neurons and neuroglia cells
Term
What are the functions of neurons?
Definition
functions to transmit nerve impulses
Term
What are the functions of neuroglia cells?
Definition
functions to support, nourish, insulate and protect neurons
Term
What are the three parts to a neuron?
Definition
cell body, dendrites and axon
Term
What does the cell body contain?
Definition
nucleus, cytoplasm, mitochondria, ribosomes and Golgi apparatus
Term
What are Nissl bodies and what are their functions?
Definition
rough endoplasmic reticulum; ribosomes on the RER are the site of protein synthesis where neurotransmitters are produced, then the endoplasmic reticulum moves the neurotransmitter through the cell
Term
What are dendrites?
Definition
nerve fibers
Term
What do dendrites transmit the impulse toward?
Definition
toward the cell body
Term
What are axons?
Definition
nerve fibers
Term
Where do axons transmit the impulse?
Definition
away from the cell body
Term
What is the axon hillock?
Definition
mound on one side of the cell body from which the axon develops
Term
What are axon terminals?
Definition
branched ends of an axon
Term
What are synaptic end bulbs?
Definition
the swollen ends of the axon terminal that contain synaptic vesicles
Term
What do the synaptic vesicles contain?
Definition
neurotransmitters
Term
What is the synaptic cleft or synaptic gap?
Definition
gap between the synaptic end knob and the other neuron or effector
Term
What are three types of neurons?
Definition
unipolar, bipolar and multipolar
Term
Name the five types of neuroglial cells we studied.
Definition
Schwann cells (neurolemmocytes), oligodendrocytes, astrocytes, microglia and ependymal cells
Term
What are Schwann cells?
Definition
myelin producing cells
Term
Where are Schwann cells located?
Definition
in the PNS
Term
What is the myelin sheath?
Definition
lipids and proteins
Term
How many Schwann cells can insulate one axon?
Definition
up to 500
Term
What effect does myelin have on speed of impulse?
Definition
increases
Term
What is the neurilemma?
Definition
the outside portion of the Schwann cell that contains the nucleus and the other cell organelles
Term
Can there be regeneration in an axon myelinated by Schwann cells?
Definition
yes
Term
What are the Nodes of Ranvier?
Definition
spaces or gaps between Schwann cells
Term
What are oligodendrocytes?
Definition
myelin producing cells
Term
Where are oligodendrocytes located?
Definition
in the CNS
Term
How many axons can one oligodendrocyte myelinate?
Definition
15
Term
Does an oligodendrocyte contain a neurilemma?
Definition
no
Term
Can there be any regeneration to an axon myelinated by oligodendrocytes?
Definition
no
Term
What is the function of astrocytes?
Definition
astrocytes connect the neuron to blood vessels as part of the blood brain barrier
Term
What is the function of microglia cells?
Definition
microglia cells are macrophages that phagocytize pathogenic microorganisms
Term
What is the function of ependymal cells?
Definition
ependymal cells line the ventricles and help to move the CSF
Term
What is white matter?
Definition
myelinated nerve fibers
Term
What part of the neuron is usually myelinated?
Definition
axon
Term
Does myelin make the impulse travel faster?
Definition
yes
Term
What is the propagation called when the axon is myelinated?
Definition
saltatory
Term
What is gray matter?
Definition
unmyelinated nerve fibers
Term
What is the propagation called in gray matter and how fast does the impulse travel?
Definition
continuous propagation; travels slower
Term
Are sensory neurons unipolar, multipolar or bipolar?
Definition
unipolar
Term
Are motor neurons unipolar, multipolar or bipolar?
Definition
multipolar
Term
Where are interneurons found?
Definition
CNS
Term
Are interneurons unipolar, multipolar or bipolar?
Definition
multipolar
Term
What do interneurons synapse with?
Definition
synapse with other interneurons or with sensory and motor neurons
Term
What is a bundle of nerve fibers in the PNS called?
Definition
nerve
Term
What is the resting membrane potential?
Definition
when the neuron is at rest and is not conducting a nervous impulse
Term
Is a resting membrane potential polarized, depolarized or repolarized?
Definition
polarized
Term
In a polarized neuron, where are the Na and K ions?
Definition
Na ions are outside the neuron and K ions are inside the neuron
Term
In a polarized neuron, what is the charge on the inside and outside of the neuron?
Definition
a positive charge on the outside and a negative charge on the inside
Term
When a neuron is depolarized, where are the Na and K ions?
Definition
Na and K ions are on the inside of the neuron
Term
What is the charge on the inside and outside of the depolarized neuron?
Definition
a positive charge on the inside and a negative charge on the outside
Term
When a neuron is repolarized, where are the Na and K ions?
Definition
Na ions are on the inside and K ions are on the outside
Term
What is the charge on the inside and outside of the repolarized neuron?
Definition
a negative charge on the inside and a positive charge on the outside
Term
What is an action potential?
Definition
an action potential is a nerve impulse (also known as depolarization/repolarization)
Term
What is the all or none response?
Definition
if the input to the neuron reaches threshold, the nerve impulse will go through the neuron to completion; if the input does not reach threshold, the nerve impulse will not be transmitted
Term
Is the action potential self propagating?
Definition
yes
Term
Does an action potential travel in only one direction?
Definition
yes
Term
Where do you find saltatory conduction?
Definition
myelinated axons
Term
Where do you find continuous conduction?
Definition
unmyelinated axons
Term
What are the four steps in the generation of an action potential?
Definition
(1) the neuron is stimulated to threshold, (2) Na ions rush into the axon causing depolarization, (3) K ions rush out of the axon causing repolarization, (4) the Na/K pump reestablishes the Na ion concentration on the outside of the neuron and the K ion concentration on the inside of the neuron
Term
What is a synapse?
Definition
functional junction between a presynaptic neuron and a post synaptic neuron or between a neuron and its effector
Term
A synapse can communicate between several things. What are they?
Definition
an interneuron and an interneuron OR a sensory neuron and an interneuron OR a neuron and an effector (muscle or gland)
Term
What is the sequence of events for a synaptic transmission?
Definition
(1) the nerve impulse reaches the synaptic knob, (2) calcium ions move into the synaptic knob and acetylcholine (ACh) is released into the synaptic cleft, (3) ACh binds to a receptor on the dendrite or cell body and causes Na channels to open causing depolarization, (4) acetycholinesterase breaks down excess ACh or ACh is taken back up by the presynaptic neuron, (5) the synaptic transmission is complete and the neuron is ready for another impulse
Term
What is the neurotransmitter in most synaptic transmissions?
Definition
the chemical that transmits the nerve impulse across the synapse to another neuron or an effector, it can be acetylcholine or norepinephrine
Term
What are the enzymes that decompose the neurotransmitters acetylcholine and norepinephrine?
Definition
acetylcholinesterase or cholinesterase
Term
Can some of the neurotransmitter be taken up into the presynaptic end bulb?
Definition
yes
Term
Why does an impulse travel in only one direction across a synapse?
Definition
only the synaptic end bulb has synaptic vesicles with the neurotransmitter which is required to initiate the impulse (the dendrite or the cell body does not have synaptic vessels with neurotransmitters)
Term
The synaptic end bulbs usually synapse to what structures on the postsynaptic neuron?
Definition
dendrite or cell body
Term
Name two principle neurotransmitters in the PNS.
Definition
acetylcholine and norepinephrine
Term
Which neurotransmitter is always released at the neuromuscular junction?
Definition
acetylcholine
Term
Which neurotransmitter is always released between the preganglionic and postganglionic fibers in the autonomic nervous system?
Definition
acetylcholine
Term
Which neurotransmitter is released at the postganglionic fiber in the parasympathetic system?
Definition
acetylcholine
Term
What neurotransmitter is released from the cholinergic fibers?
Definition
acetylcholine
Term
What neurotransmitter is released from the adrenergic fibers?
Definition
norepinephrine or epinephrine
Term
What neurotransmitter is released from the postganglionic fiber in the sympathetic nervous system?
Definition
epinephrine
Term
Name three CNS neurotransmitters.
Definition
norepinephrine, serotonin, dopamine
Term
Which one of these three causes severe depression if there is inadequate production: norepinephrine, serotonin or dopamine?
Definition
serotonin
Term
Which CNS neurotransmitter does prozac inhibit the reuptake of?
Definition
serotonin
Term
Which CNS neurotransmitter causes symptoms of Parkinson’s disease if there is inadequate production?
Definition
dopamine
Term
What are substances that alter the neuron’s response to a neurotransmitter or block the release of a neurotransmitter?
Definition
neuromodulators
Term
What is the general term of neuromodulators that inhibit substance P?
Definition
endorphins
Term
What does substance P relay?
Definition
pain
Term
What drug is structurally related to our natural endorphins?
Definition
morphine
Term
What is a reflex?
Definition
automatic, unconscious, unlearned, involuntary, built in behavior
Term
What is a nerve pathway?
Definition
the pathway that a nervous impulse takes as it goes through the nervous system
Term
What is a reflex pathway?
Definition
the simplest nerve pathway
Term
What are some examples of somatic reflexes? Are they involuntary?
Definition
blinking, ducking, knee jerk, withdrawal; yes
Term
What are some examples of autonomic reflexes? Are they involuntary?
Definition
blood pressure, heart rate, respiratory rate; yes
Term
What are the five components of a reflex arc?
Definition
receptor, sensory neuron, interneuron, motor neuron, effector
Term
How many neurons are in a knee-jerk reflex?
Definition
2
Term
How many neurons are in a withdrawal reflex?
Definition
3
Term
What is a reflex with one synapse called?
Definition
monosynaptic reflex
Term
What is a reflex with more than one synapse called?
Definition
polysynaptic reflex
Term
List four ways that the CNS is protected.
Definition
bones of the cranium and vertebrae, meninges, CSF, blood brain barrier
Term
List the meninges from outermost to innermost.
Definition
dura mater, arachnoid mater, pia mater
Term
What does the dura mater take the place of in the cranium?
Definition
periosteum
Term
What makes up the epidural space and where is it located?
Definition
adipose tissue and blood vessels; located between the bones of the vertebrae and the dura mater
Term
What are the blood-filled channels formed by splitting the dura mater?
Definition
dual sinus or superior sagittal sinus
Term
Where is the subarachnoid space; what is located there?
Definition
located between the arachnoid mater and the pia mater; CSF
Term
What is the function of the pia mater?
Definition
follows every contour of the brain and the spinal cord and provides nourishment for them
Term
Where is CSF located and what is CSF?
Definition
ventricles and canals (subarachnoid space and the central canal) of the CNS; CSF is a clear, colorless liquid with a composition very similar to plasma
Term
What produces the CSF and where are they located?
Definition
choroid plexus; located in the ventricles of the brain
Term
What are the functions of the CSF?
Definition
supports and protects the brain, acts as an shock absorber, transports nutrients, hormones and waste products
Term
Where does the CSF reenter the blood?
Definition
dural sinus or superior sagittal sinus
Term
When astrocytes permit certain substances to enter the brain tissue and prevent others, what is this called?
Definition
blood brain barrier
Term
Name the four parts of the brain.
Definition
cerebrum, cerebellum, diencephalon, brain stem
Term
What is the largest part of the brain?
Definition
cerebrum
Term
What separates the cerebrum into two halves?
Definition
longitudinal fissure
Term
What are the two halves of the cerebrum called?
Definition
right and left hemispheres
Term
What separates the cerebrum from the cerebellum?
Definition
transverse fissure
Term
What connects the cerebrum?
Definition
corpus callosum
Term
What are the shallow grooves (in the cerebrum) called?
Definition
sulci
Term
What are the ridges (in the cerebrum) called?
Definition
gyri
Term
What are the functions of the cerebrum?
Definition
conscious thought, memory, creativity, personality, primary motor cortex (initiating voluntary muscular movement), primary sensory cortex (receives and interprets sensory impulses from the skin), receives sensory impulses from special senses on specific lobes
Term
Name the four lobes located on the cerebrum and give their functions.
Definition
frontal lobe – problem solving; temporal lobe – hearing; parietal lobe – understanding words; occipital lobe – sight
Term
Where is white matter located in the cerebrum? Why is it white?
Definition
in the interior of the cerebrum; it is white because it consist of myelinated nerve fibers
Term
Name the fiber that transmits the impulse between convolutions in the same hemisphere.
Definition
association fibers
Term
Name the fiber that transmits the impulse from one hemisphere to the other.
Definition
commissural fibers
Term
Name the fiber that transmits impulses from the cerebrum to others parts of the brain or spinal cord.
Definition
projection fibers
Term
Where is the gray matter located in the cerebrum?Why is it gray?
Definition
the edge of the cerebrum known as the cortex; it is gray because it consist of unmyelinated fibers
Term
If you stimulate a specific motor neuron here, you generate a contraction in a specific skeletal muscle. Name this place.
Definition
primary motor cortex
Term
What is the region on the parietal lobe that receives somatic sensory information from touch, pressure, pain, vibration, etc.?
Definition
primary sensory cortex
Term
What is the area that interprets and integrates incoming data to coordinate a motor response?
Definition
association areas
Term
What is the cerebral cortex?
Definition
the outer edge 3 mm of the cerebrum where the interneurons are unmyelinated; where you have consciousness of sensory impulses and where you initiate voluntary skeletal muscle contractions; this is what makes you human
Term
Name the three areas of the cerebral cortex and give the function of each.
Definition
sensory areas are located on all lobes that receive sensory information from the skin and sensory organs; motor areas are located on the frontal lobes and send out voluntary muscle commands; association areas integrate, interpret, analyze and store memory and then retrieves the information to try to decide what to do with it
Term
What is the second largest part of the brain?
Definition
cerebellum
Term
What are the functions of the cerebellum?
Definition
balance, posture, muscle tone, mediates subconscious contractions of skeletal muscles for smooth coordination of skeletal muscles
Term
How are the messages sent from the cerebrum to the cerebellum to carry out the functions of the cerebellum?
Definition
First – the cerebral cortex (primary motor cortex) sends a message to the skeletal muscle and tells it what to do and at the same time sends the same message to the cerebellum and tells the cerebellum what the muscle is suppose to do
Term
What are the two parts of the diencephalon?
Definition
thalamus and hypothalamus
Term
What is the function of the thalamus?
Definition
relay station
Term
List the functions of the hypothalamus.
Definition
thirst center, temperature center, hunger center, sex center, and it connects the nervous system with the endocrine system
Term
Name the parts of the brain stem from superior to inferior.
Definition
midbrain, pons, medulla oblongata
Term
What is the function of the midbrain?
Definition
reflex center for auditory and visual stimuli
Term
What is the function of the pons?
Definition
it is a bridge, it transmits nervous impulses from the cerebrum to the cerebellum and from the cerebrum to the brain stem
Term
Where does crossing over occur?
Definition
medulla oblongata
Term
What three centers are located in the medulla oblongata and what do they control?
Definition
cardiac center – controls heart rate; respiratory center – controls respiratory rate; vasomotor center – controls blood pressure
Term
What is the “emotional brain”?
Definition
limbic system
Term
What are the nerve fibers in the brain stem that activate the cerebral cortex?
Definition
reticular formation
Term
If reticular formation decreases in activity, what results?
Definition
sleep
Term
If the reticular formation ceases to function, what results?
Definition
coma
Term
Can the cerebral cortex activate the reticular formation?
Definition
yes; wakes you up in the middle of the night and then you can not go back to sleep
Term
The spinal cord consists of gray and white matter. Where does integration of reflexes occur?
Definition
gray mater
Term
Where are the ascending and descending tracts located?
Definition
white mater
Term
What tracts carry sensory information toward the brain?
Definition
ascending tracts
Term
What tracts carry motor information away from the brain?
Definition
descending tracts
Term
What is a bundle of axons located in the CNS?
Definition
tracts
Term
Which roots contain axons of motor neurons?
Definition
ventral roots
Term
Which roots contain cell bodies of sensory neurons?
Definition
dorsal root ganglion
Term
Describe the pathway of an ascending sensory tract starting with the stimulus and ending with perception.
Definition
receptor to sensory neuron to interneuron with crossing over occurring in the medulla oblongata then to the thalamus to the sensory cortex where conscious perception of the stimulus occurs
Term
What is the tapered, conical end of the spinal cord called?
Definition
medullary cone (conus medullaris)
Term
What is the long ventral and dorsal roots of the spinal segments L2 to S5 called?
Definition
cauda equina
Term
What is the epidural space?
Definition
adipose tissue and blood vessels that cushion the spinal cord between the vertebrae and the dura mater
Term
What are the 2 principle functions of the spinal cord?
Definition
serve as the integrating center for spinal reflexes and conduct impulses up and down the CNS via ascending tracts and descending tracts
Term
Which system is concerned with voluntary action of the skeletal muscles?
Definition
SNS
Term
Which system coordinates cardiovascular, respiratory, digestive, excretory and reproductive functions?
Definition
ANS
Term
Which system has only one motor neuron? Where does this neuron synapse?
Definition
SNS; at the effector which is skeletal muscle
Term
Which system has two motor neurons?
Definition
ANS
Term
What are the two motor neurons from the ANS system called?
Definition
preganglionic motor neuron and postganglionic motor neuron
Term
Where is the cell body of the preganglionic nerve fiber located?
Definition
inside the spinal cord
Term
Where does the pre and postganglionic nerve fiber synapse?
Definition
in the sympathetic division it occurs at the synaptic trunk or the paravertebral ganglion
Term
Where does the axon of the postganglionic nerve go?
Definition
to the effector – either cardiac muscle, smooth muscle or glands
Term
In which system are the sensations consciously perceived?
Definition
SNS
Term
In which system is the sensory information not consciously perceived?
Definition
ANS
Term
Which system contains cranial and spinal nerves?
Definition
both SNS and ANS
Term
Which system is divided into 2 principle division?
Definition
ANS
Term
Do the two principle divisions of the ANS usually have opposite effects?
Definition
yes
Term
What are the 2 systems that make up the PNS?
Definition
ANS and SNS
Term
Which system is concerned with consciously perceived sensations ANS or SNS?
Definition
SNS
Term
What are the effectors in the SNS?
Definition
skeletal muscles
Term
How many motor neurons are in the SNS?
Definition
one
Term
Which system is concerned with sensations that are not consciously perceived?
Definition
ANS
Term
How many motor neurons are in the ANS?
Definition
two
Term
What are the effectors in the ANS?
Definition
cardiac muscle, smooth muscles and glands
Term
What are the 2 divisions of the ANS?
Definition
sympathetic and parasympathetic divisions
Term
Which division is known as the thoracolumbar division?
Definition
sympathetic division
Term
Which division is concerned with “fight or flight” situations?
Definition
sympathetic division
Term
What does the sympathetic division stimulate and inhibit?
Definition
the sympathetic division stimulates heart rate, respiratory rate, the liver to convert glycogen to glucose, increases blood pressure and dilates the pupils; while it inhibits the GI tract, salivary glands, the urinary system and the reproductive system
Term
In the sympathetic division, where do the preganglionic and postganglionic neurons synapse?
Definition
the sympathetic trunk or the paravertebral ganglion
Term
Which neurotransmitter is usually released at the pre/postganglionic synapse in the sympathetic division?
Definition
acetylcholine
Term
Which neurotransmitter is usually released at the postganglionic synapse?
Definition
epinephrine
Term
Name the receptors on the effector membrane in the sympathetic division?
Definition
alpha and beta receptors
Term
The adrenal medulla releases which hormones?
Definition
epinephrine
Term
What effects does the hormone epinephrine have?
Definition
sustains the sympathetic effect
Term
Which division is known as the craniosacral division?
Definition
parasympathetic division
Term
Which division is concerned with rest and restore?
Definition
parasympathetic division
Term
What does the parasympathetic division stimulate and inhibit?
Definition
the parasympathetic division stimulates the salivary glands to secrete and increases the GI tract movement, stimulates the urinary and reproductive systems; while it inhibits heart rate, respiratory rate, blood pressure, and causes the pupils to constrict and causes the liver to convert glucose to glycogen
Term
In the parasympathetic division, where do the preganglionic and postganglionic neurons synapse?
Definition
terminal ganglion
Term
Which neurotransmitter is released at the pre/postganglionic synapse?
Definition
acetylcholine
Term
Which neurotransmitter is released at the postganglionic synapse?
Definition
acetylcholine
Term
Which nerve provides 75% of the entire parasympathetic outflow?
Definition
vagus nerve
Term
What are the receptors on the parasympathetic effectors?
Definition
nicotinic and muscarinic
Supporting users have an ad free experience!