Module 11 - Nervous System Flashcards
The receptors of the nervous system are _________, receiving many types of sensations.
Sensory receptors
The _________ of the central nervous system is the brain.
Control center
Pathways into the central nervous system are called ________.
Afferent
Pathways out of the central nervous system are called ________.
Efferent
________ information is received in the internal or external environment and, through a process called transduction, is converted to a form the nervous system can use.
Sensory
Peripheral nervous system (PNS) is comprised of:
Cranial nerves III-XII Spinal nerves Ganglia Enteric plexuses Sensory receptors
The ________ comprises those effectors which are not under conscious control.
Autonomic motor system (ANS)
The central nervous system is comprised of:
The brain
The spinal cord
A ________ is a collection of nerve cell bodies in the PNS.
Ganglion
A _______ is a collection of nerve cell bodies in the CNS.
Nucleus
The walls of digestive organs have a network of neurons in an arrangement called a ________.
Plexus
________ are the cells that receive, process and transmit information in a point to point fashion in the nervous system.
Neurons
________ maintain the structural and chemical environment of the brain, and function in ways we probably don’t fully appreciate.
Glial cells
What are the four types of glial cells?
Astrocytes
Oligodendrocytes
Microglia
Ependymal cells
_______ form the borders of the CNS.
HINT: forms the pia mater, A thin membrane covering the brain
HINT: with endothelial cells of capillaries, form blood brain barrier which keeps certain substances out of CNS
HINT: “Sponge up” excess ions and toxins
Astrocytes
_________ forms myelin sheaths which insulate nerve axons that must send information over long distances.
Oligodendrocytes
_______ are the brains equivalent of macrophages.
HINT: immune defense
Microglia
________, along with the border – forming astrocytes, make up a single layer of border cells lining the ventricles.
HINT: make cerebrospinal fluid
Ependymal cells
What are the 2 types of glial cells?
Satellite cells
Schwann cells
________ in the PNS perform the same basic functions as astrocytes in the CNS: maintenance of a favorable chemical environment and mechanical/structural support. Mostly found in ganglia, collections of nerve cell bodies in the PNS.
Satellite cells
_________ are found in the PNS in place of the oligodendrocytes of the CNS.
Schwann cells
A bundle of axons all traveling together in the peripheral nervous system (PNS).
Nerve
A bundle of axons all traveling together in the central nervous system (CNS).
Tract
___________: all atoms want to move from high concentration to low concentration.
Concentration forces
__________: positive ions want to be where there are excess negative charges. Negative ions want to be where there are excess positive charges.
Electrical forces
The __________ is the voltage at which the chemical and electrical forces are equal and opposite.
Equilibrium potential
The _________ of a neuron is maintained by leak channels.
Resting potential
The _________ is used to send information over long distances through axons
Action potential
The _________ results from the opening and closing of voltage gated channels.
Action potential
What are the steps in the action potential?
- Resting potential
- Threshold
- Depolarization
- Peak
- Repolarization
- After hyperpolarization
- Return to resting potential
Action potential begins at the __________.
Trigger zone
A _______ is where neurons send information to other neurons or to an effector cell.
Synapse
When ________ binds to its receptor, the receptor changes shape and opens a pore.
Ligand
________ are gated channels that randomly open and close
Leakage channels
_________ are gated channels that open in response to the binding of a ligand (chemical) stimulus.
Ligand-gated channels
_________ are gated channels that open in response to mechanical stimulus.
Mechanically gated channels
___________ are gated channels that open in response to a voltage stimulus (change in membrane potential).
Voltage gated channels
Receptors for chemicals like neurotransmitters or drugs
Logan’s-gated channels
Essential for action potentials or synapses.
Voltage gated channels
________ is defined as any change in the neuron which makes it more difficult to reach threshold.
Inhibition
________ neurotransmitter receptors cause a change in the ionic environment of the neuron.
Ionotropic
___________ neurotransmitter receptors cause a change in the biochemical environment of the neuron.
Metabotropic
Inputs such as pH of blood, body temperature, blood Ca++ levels, and outputs like increased heart rate, increased salivation, contraction of skeletal muscles etc. are all monitored by the _________ System.
Nervous
In the nervous system feedback loop, the light-sensitive cells of the retina in the eye would be an example of a __________ in the nervous system.
Receptor (sensory)
In the nervous system feedback loop, the tissue/organ that carries out a desired function is called a/an __________.
Effector (motor)
In the nervous system feedback loop, the spinal cord, medulla, pons, and midbrain are a few of the structures of the nervous system that are part of the _________ __________.
Control center
Because they bring information to the CNS, sensory pathways are _________.
Afferent
Because they take information from the CNS, motor pathways are ___________.
Efferent
The motor division of the somatic nervous system controls contraction of ________ ________.
Skeletal muscles
The motor division of the _________ nervous system controls glandular secretions and smooth muscle contraction.
Autonomic
Leakage channels have the same probability of being open (or closed), regardless of whether the neuron is generating an ________ _________.
Action potential
The parasympathetic and sympathetic are subdivisions of the _________ nervous system.
Autonomic
The brain and spinal cord are organs of the _______ ________ ________.
Central nervous system
A ________ is a collection of nerve cell bodies in the peripheral nervous system.
Ganglion
A ________ is a collection of nerve cell bodies in the central nervous system.
Nucleus
__________ are the cells of the nervous system that receives, process, and send information.
Neurons
Ependymal cells are a type of ________ in the CNS.
Glia cell
Schwann cells in the peripheral nervous system form __________.
Myelinated sheaths
Astrocytes in the central nervous system are analogous to ________ cells in the peripheral nervous system.
Satellite
Tracts are bundles of axons found in the _________ _________ System.
Central nervous
Bundles of axons in the peripheral nervous system are called __________.
Nerves
Voltage gated channels propagate _________ _______ along axons.
Action potentials
A ___________ triggers a small positive voltage change in a sensory neuron.
Stimulus
Depolarization of a neuron occurs when ________ channels open.
Sodium
The repolarizing phase is when the membrane voltage falls to a negative value, close to the equilibrium potential of ________.
Potassium
When the membrane potential goes below the average resting potential, _________ has occurred.
Hyperpolarization
Inhibitory postsynaptic potential (IPSP) in a postsynaptic membrane causes the cell to become more _________.
Negative
Excitatory postsynaptic potential (EPSP) in a postsynaptic membrane causes the cell to become more ________.
Positive
Ligand-gated channels would be expected to predominate neuronal ___________.
Dendrites and cell bodies
Voltage gated channels would be expected to predominate in neuronal _________.
Axons
Ligand-gates channels are generally affected by _______ and __________.
Drugs; neurotransmitters
What is the major role of the glial cells?
Structure and nutrition of the brain
Voltage gated channels are proteins that change _________ during the action potential.
Shape
Alpha motor neurons control contraction of ________ _________ in the somatic nervous system.
Skeletal muscles
When potassium channels are open in the intracellular membrane potential would be more ________.
Negative
When the sodium channels are open in the intracellular membrane potential would be more _________.
Positive
Hyperpolarization of a postsynaptic membrane is the result of an ________.
IPSP (inhibitory postsynaptic potential)
Depolarization of a postsynaptic membrane is the result of an _______.
EPSP (excitatory postsynaptic potential)
Spatial summation is described as many EPSPs or IPSPs arriving at a similar _________.
Location
Temporal summation describes many EPSPs or IPSPs arriving at a similar ________.
Time
Opening of ligand-gated sodium channels would result in the generation of a ___________.
EPSP
Opening of ligand-gated potassium channels would result in the generation of a ________.
IPSP
Graded potential’s (IPSPs and EPSPs) will travel _______ distances.
Short
Typical characteristics of graded potentials (IPSPs and EPSPs) would include:
- Occur in dendrites and cell bodies
- Ligand or mechanically gated channels
- Longer duration
- Shorter distance
- Usually occurs summation
Typical characteristics of action potentials would include:
- Occur at trigger zone in a long axons
- Sodium/potassium voltage gated channels
- Longer distances
- Shorter duration
- Occurs without summation (all or nothing)
Neurotransmitters such as aspartate and glutamate are _______ amino acids.
Unmodified
Neurotransmitters such as epinephrine (adrenaline) and serotonin are ________ amino acids.
Modified
Structurally, substance P is a __________.
Polypeptide neurotransmitter
At normal body temperature, nitric oxide (NO) is a ___________.
Excitatory neurotransmitter
Norepinephrine (noradrenaline) functions to promote the flight or fight response and will _______ blood pressure.
Raise
Dopamine is a biogenic amine that will facilitate coordinated/smooth _________.
Movements
Serotonin (5-hydroxytryptamine) is a biogenic amine that regulates ________.
Mood
Acetylcholine is most often an ________ neurotransmitter.
Excitatory
Acetylcholine is an __________ neurotransmitter when potassium channels of the postsynaptic cell open.
Inhibitory
Ionotropic receptors are those that ________ and ________ channels.
Open; close
Metabotropic receptors change the _________ of a neuron.
Biochemical environment
