Chapter 7 Nervous System Flashcards
Nervous tissue functions to ____________
conduct messages throughout the body.
Nervous system includes: _________
Includes nerve tissue and sense organs
Nervous system functions to:
Senses environment – receives information from both outside and inside the body Processes the information it receives Respond to information – sends out orders
Central Nervous System (CNS) consists of _____
Brain and Spinal Cord
Peripheral Nervous System (PNS) consists of ______
Nervous tissue outside brain and spinal cord
Sense organs
What are the two types of nervous tissue cells?
Neurons and Neuroglial cells
_____ are the cells that are responsible for
transmitting messages
neurons
_____ are cells that support the neurons
Neuroglial cells
What are the two Divisions of the Nervous System?
- Central Nervous System (CNS)
2. Peripheral Nervous System (PNS)
What are the different types of Neuroglial cells ?
Microglia
Astrocytes
Oligodenrocytes
Schwann cells
_____ are immune system cells, engulf bacteria and cellular debris
Microglia
______ provide nutrients to neurons
Astrocytes
_____ and ______ form myelin sheaths
Oligodenrocytes and Schwann cells
What are the different parts of the neuron?
Cell body, dendrites, axons
_____ contains the nucleus, main body
of cell
cell body
______ are projections from the cell body that carry messages to the cell body
Dendrites
_____ are one large projection that carry messages away from the cell body
Axon
Neurons in the _____ are either carrying messages to or from the CNS
Peripheral Nervous System (PNS)
Neurons in the PNS are either carrying messages ____ or ____ the CNS
to, from
Afferent = ___________ = Neurons carrying
messages to the CNS
Sensory neurons
Afferent = Sensory neurons = Neurons carrying
messages to the______
Central Nervous System (CNS)
Efferent = _________ = Neurons carrying messages from the CNS
Motor neurons
Efferent = _________ = Neurons carrying messages _____ the CNS
from
_____ are located between sensory and motor neurons within the CNS
Interneurons
Interneurons are located between ______ and ______ neurons within the CNS
sensory and motor neurons
Interneurons are located between sensory and motor neurons within the ____
CNS
Interneurons ______ and ________ sensory signals
integrate and interpret
Interneurons integrate and interpret _______ signals
sensory
The afferent or sensory neuron cell bodies are located in ________.
dorsal root ganglion
The _________ neuron cell bodies are located in dorsal root ganglion.
afferent or sensory
The efferent or motor neuron cell bodies are located in the _______
gray matter of the spinal cord
__________ neuron cell bodies are located in the gray matter of the spinal cord.
The efferent or motor
The axons of motor neurons leave the _____ and go to the ________
CNS, skeletal muscles
Neurons that have axons covered with _______ that contain the protein myelin are called ________
neuroglial cells, myelinated neurons
________ are able to carry messages faster than non-myelinated neurons
Myelinated neurons
The main benefit of myelin sheaths is :
that myelinated neurons are able to carry
messages faster than non-myelinated neurons
Myelin sheaths from Schwann cells also help with what?
regenerate injured PNS neuron axons
Schwann cells and Oligodendrocytes are wrapped around _______
neuronal axons
Schwann cells are found in the ______
PNS
Oligodendrocytes are found in the _____
CNS
_________ are spaces on the axon between the glial cells
Nodes of Ranvier
Nodes of Ranvier are spaces on the axon between the _____
glial cells
Multiple Sclerosis (MS) is caused by ______
Caused by the destruction of the myelin sheath that surrounds axons found in the CNS
Multiple Sclerosis (MS) is Caused by the destruction of the myelin sheath that surrounds axons found in the \_\_\_\_\_
CNS
Multiple Sclerosis (MS) can result in:
paralysis and loss of sensation, including loss of vision
Nerve contain ______ are bundled together
Neuron axons
The bundles of nerves containing neuron axons contain the following parts?
Axons
Blood vessels
Connective tissue
A nerve impulse, or action potential, involves _______ and ________ that cross the cell membrane through the ion channels
sodium ions (Na+), potassium ions (K+)
What is membrane potential?
The difference in charge between the inside
and outside of the neuron is the membrane
potential
A neuron that is not conducting a message is
said to be _______
“Resting”
When a neuron is resting there is more ________ outside the neuron cell and more _______ inside the cell
sodium (Na+), potassium (K+)
The inside of the cell has a ________ charge compared to the outside the cell
negative
To maintain this resting membrane potential the neuron pumps ____ out of the cell and _____ into the cell.
Na+, K+
In the Sodium Potassium Pump, The transport proteins take ____ Na+ ions out for every______ K+ ions into the cell = Na+/K+ pump
3, 2
The Sodium Potassium Pump is an example of ______
Active Transport
Does the Sodium Potassium Pump Require ATP?
Yes
An electrochemical signal conducted along an axon. It is a wave of ________ followed by ________
depolarization, repolarization
________ is caused by sodium ions entering the axon
Depolarization
Depolarization is caused by ______ ions entering the axon
sodium
________ is caused by potassium ions leaving axon
Repolarization
Repolarization is caused by ______ ions leaving axon
potassium
In Step 1 of the action potential :
The axon is ______ when voltage gated sodium ion channels open and Na+ comes rushing in, causing the inside of the neuron to become ________ charged
depolarized, positively charged
In Step 2 of the action potential :
The axon is repolarized when voltage gated ______ ion channels open up and allow ____ to go out of the axon. This returns the membrane potential to be
negative on the inside of the neuron
potassium, K+
In Step 2 of the action potential :
The action potential ______ the axon
travels down
After the action potential, the sodium potassium pump ________ by pumping sodium (Na+) out of the cell and potassium (K+) back into the cell
restores the original conditions
Action potentials are an ________
all or nothing response
The level of the action potential is _______
always the same
In action potential, the direction is always _________ the
axon
one way down
The direction is always one way down the axon. The sodium channels are
inactivated for awhile after the action potential passes this is called the ______
refractory period
The junction between two neurons or between a neuron and a muscle is called a ______
synapse
What are the 3 components of the synapse?
Presynaptic neuron, postsynaptic neuron, synaptic cleft
_______ neuron is the transmitting neuron
Presynaptic
________ neuron is the receiving neuron or the muscle
postsynaptic
the gap in between the presynaptic and postsynaptic neuron is called the _____
synaptic cleft
Presynaptic neuron has ________ that contain neurotransmitters
synaptic vesicles
Acetylcholine Acts in both the PNS and the CNS as a
_______
neurotransmitter
Acetylcholine causes _______ muscles to contract
voluntary
Myasthenia gravis is an autoimmune disease that __________
attacks the acetylcholine receptors, resulting in reduced muscle strength
Oxygen will be transported by:
- Simple diffusion
- Facilitated diffusion
- Active transport
- Both 2 and 3
- All of the above
- Simple diffusion
glucose can be transported by:
- Simple diffusion
- Facilitated diffusion
- Active transport
- Both 2 and 3
- All of the above
- Both 2 and 3
Amino acids can be transported by:
- Simple diffusion
- Facilitated diffusion
- Active transport
- Both 2 and 3
- All of the above
- Both 2 and 3
Steroids can be transported by:
- Simple diffusion
- Facilitated diffusion
- Active transport
- Both 2 and 3
- All of the above
- Simple diffusion
Which type of neuron is found only in the brain and spinal cord?
interneuron
glial cell
sensory neuron
motor neuron
interneuron
Motor neurons conduct messages from the spinal cord to the muscles or glands, these would be _____ neurons.
afferent
efferent
efferent
Schwann cells form myelinated sheaths in the ____ nervous system.
peripherial
central
peripherial
The cell bodies of motor neurons are located in the ____.
spinal cord
dorsal root ganglion
spinal cord
In myelinated neurons, nerve impulses jump from one exposed region of the axon to another. This exposed region is called the ________.
interneurons
node of Ranvier
motor end plate
Schwann cell gap
node of Ranvier
Which of these diseases involves the destruction of the myelin sheath on certain neurons within the brain and spinal cord?
Parkinson’s disease
depression
multiple sclerosis
Alzheimer’s disease
multiple sclerosis
When a neuron is resting, this ion has a greater concentration outside the cell:
calcium
chloride
potassium
sodium
sodium
During depolarization, this ion enters/leaves the cell:
potassium enters chloride enters chloride leaves potassium leaves sodium leaves sodium enters
sodium enters
During repolarization, the inside of the cell is becoming
more positive
more negative
more negative
Which ion triggers the release of neurotransmitters?
sodium
chloride
calcium
potassium
calcium
What is the name of the neurotransmitter that acts in both the CNS and PNS?
Acetylcholine
What ion has to be present in order for the vesicles to release the neurotransmitters (acetylcholine) into the synaptic cleft?
Calcium
Once Acetylcholine is released into the synaptic cleft, what do they bind to, and why?
They bind to receptors on the postsynaptic neuron/muscle they generate the next action
potential because they cause the sodium ion channels to open up
What happens to the Acetylcholine once the action potential has been generated?
Destroy them with enzymes or reuptake
The inside of the neuron becomes more _____ when it is depolarizing?
e. Negative
f. Neutral
g. Balanced
h. Positive
Positive
What are the steps in Transmission across synaptic cleft
- The action potential gets to the end of the
presynaptic axon - The action potential triggers Ca2+ to enter
the presynaptic axon terminal - The Ca2+ triggers synaptic vesicles located
at the axon terminal to merge with the
neural membrane - The synaptic vesicles release the
neurotransmitters into the synaptic cleft - These neurotransmitters travel across the
synaptic cleft to the postsynaptic neuron
(or the muscle) - Neurotransmitter binds to receptors on the
postsynaptic neuron (or muscle) - These receptors are ligand gated sodium ion
channels which allow Na+ to enter the
postsynaptic neuron (or muscle) and triggers
an action potential in the postsynaptic neuron
(or muscle contraction) - Once the neurotransmitters are released they
need to be destroyed or contained quickly or
they will continue to stimulate the nerve