Introduction to nervous system Flashcards
What are the functions of the nervous system?
There are 3
Sensory input
Integration
Motor output
What type functions of the nervous system is this? _____- Monitoring stimuli occurring inside and outside the body.
Sensory input
What type functions of the nervous system is this?
____- Processing of sensory input and formulation of motor commands.
Integration
What type functions of the nervous system is this?
____- Response to stimuli by activating effector organs.
Motor output
What is the organization of the nervous system?
The are 2
Central nervous system (CNS)
Peripheral nervous system (PNS)
Define the reflexes?
predictable rapid response to a stimulus
What are the components of reflex?
There are 5
Receptor Sensory neuron Control center Motor neuron Effector
What type of component of reflex is this?
_____- detect stimulus
Receptor
What type of component of reflex is this?
______- Relays info to CNS (Afferent pathway)
Sensory neuron
What type of component of reflex is this?
_____- Region of the CNS that processes sensory information and sends motor commands
Control center
What type of component of reflex is this?
_____- Carries motor commands away from the CNS to the effector ( Efferent pathway )
Motor neuron
What type of component of reflex is this?
_____-Muscle or gland that responds to motror commands by producing the response
Effector
What are the divisions of PNS? There are 5 Mnemonic device: Alidio Says value sound excellent
Afferent fibers (sensory) division Somatic afferent fibers Visceral afferent fibers Special sensory afferent fibers Efferent ( motor) division
What type of divisions of PNS is this?
____- Carry info from receptors to the CNS
-Alidio
Afferent fibers (sensory) division
What type of divisions of PNS is this?
____- Carries impulses from skin, skeletal muscle and joints
-says
Somatic afferent fibers
What type of divisions of PNS is this?
____- Carries impulses from organ within ventral body cavities
-value
Visceral afferent fibers
What type of divisions of PNS is this?
_____- Carries impulses from nose eye tongue and ear.
-sounds
Special sensory afferent fibers
What type of divisions of PNS is this?
_____- Motor neurons carry commands away from CNS
-excellent
Efferent (motor) division
Categorized by what effectors is controlled:
There is 2
Somatic efferent fibers
Autonomic efferent fibers
What type is Categorized by what effectors is controlled:
______-Control voluntary skeletal muscle contraction
Somatic efferent fibers
What type is Categorized by what effectors is controlled:
________-Control involuntary cardiac muscle, smooth muscle, and glands.
Autonomic efferent fibers
Further subdivided into two divisions by the location they emerge from the CNS and function:
There are 2
Sympathetic division
Parasympathetic division
What are the structure of a typical neuron:
There are 7
Soma Dendrites Axon hillock Axon Axolemma Myelin Axon terminale
What structure of a typical neuron is this?
_____- Contains nucleus and organelles
Soma ( Cell body or perikaryon)
What structure of a typical neuron is this?
_____- Branching extensions that contain receptors to detect neurotransmitters from other neurons.
Dendrites
What structure of a typical neuron is this?
______- Where the cell body tapers into the axon, site where the action potential originates.
Axon Hillock
What structure of a typical neuron is this?
______- Single long process, transmits action potential away from soma
Axon
What structure of a typical neuron is this?
______- Plasma membrane of an axon
Axolemma
What structure of a typical neuron is this?
_____- insulation formed by glial cells wrapping around the axon
1) Nodes of Ranvier
2) Internodes
Myelin sheath
______ gaps in the myelin sheath
Nodes of Ranvier
_______ Segments of myelin
Internodes
What structure of a typical neuron is this?
______- enlarged distal ends of an axon that contain secretory vesicles filled with neurotransmitters (Synaptic vesicles)
Axon terminale
What are the different types of Functional Classification of Neurons?
Sensory (afferent) neurons
Interneurons
Motor (efferent) neurons
What type of Functional Classification of Neurons is this?
_____- Carry sensory information from the sensory receptor to CNS
Sensory ( afferent) neurons
What type of Functional Classification of Neurons is this?
_____- (association) between sensory and motor neurons, only in CNS.
Interneurons
What type of Functional Classification of Neurons is this?
_____-carry commands from CNS to effector organs
Motor (efferent) neurons
What are the structural classification of neurons?
There are 3
Multipolar neurons
Unipolar neuron
Bipolar neuron
What type of structural classification of neurons is this?
______-Multiple processes branching off the cell body, numerous dendrites and one axon.
Multipolar neuron
What type of structural classification of neurons is this?
______- appear to have one extension off the extension off the cell body. This extension branches forming a long axon with dendrites on one end and axon terminal on the opposite end.
Unipolar neuron
“pseudounipolar” - are called in humans
What type of structural classification of neurons is this?
______- Two extensions from cell body, one dendrite & one axon. Found in special sense organs.
* Examples: Afferent neurons in the pathways for the special senses vision, hearing, and smell. Bipolar cells of the retina receives visual information from photoreceptors. Bipolar cells of the spiral ganglion in the cochlea receive auditory information from auditory hair cells. Olfactory receptor neurons in the superior nasal cavity detect odorants.
Bipolar neuron
______- cells that surrounds and support neurons
Neuroglia (glia)
Types of neuroglial cells of the CNS:
Mneumonic device
All
Of
My
Elephants
Astrocytes cells
Oligodendrocytes cells
Microglia cells
ependymal cells
What type of neuroglial cells of the CNS is this?
____- Star shaped, processes cling to neurons and capillaries.
Astrocytes cells
Astrocytes cells
_____- Anchor neurons to surrounding tissues and capillaries.
Provide structural support
Astrocytes cells
_____- Feet wrap around capillaries and controls uptake of selected materials from the blood.
Maintain blood brain barrier
Astrocytes cells
_____- Recaptures released neurotransmitters and leaked ions.
Adjust interstitial environment
Astrocytes cells
_____- Directs growth of neurons and synapse formation.
Guides neuron development
What type of neuroglial cells of the CNS is this?
_____- wrap cytoplasmic processes around the axons of neurons
*Forms a white fatty insulation material called a myelin sheath
Oligodendrocytes cells
What type of neuroglial cells of the CNS is this?
_______- oval cells with long thorny processes
*Removes cellular debris and pathogens
Microglia cells
What type of neuroglial cells of the CNS is this?
_____- Ciliated cells, line cambers filled with cerebrospinal fluid
*Monitor and maiintain the composition o CSF
*Assit in the circulation of CSF
Ependymal cells
Types of Neuroglial cells in the PNS;
Schwann cells and
Satellite cells
What type of neuroglial cells in the PNS is this?
_____- Surrounds and protects axons in the PNS
*Forms myelin sheath around some axon of PNS
* ____- an outer layer that contains Schwann cell cytoplasm.
Schwann cells
What type of neuroglial cells in the PNS is this?
_____- Surrounds cell bodies of neurons a. Isolates the cell body and regulates the exchange of nutrients and waste.
Satellite cells
The first step for how information is transmitted through the nervous system
_____- separation of charge across the plasma membrane measured in volts.
Membrane potential
The second step for how information is transmitted through the nervous system
________- Membrane potential at rest when the cell is not receiving information in the form of graded potential or sending out information as an action potential. Resting potential is typically around -70 mV.
Resting membrane potential
The Third step for how information is transmitted through the nervous system
_______- higher {Na+} outside cell higher {k+} inside cell
Chemical gradients
The fourth step for how information is transmitted through the nervous system
______- The membrane potential becomes less negative
*When neurons are stimulated Na+ channels open and Na+ rushes into the cells.
Depolarization
The fifth step for how information is transmitted through the nervous system
______- a localized change in membrane potential that is short-lived and dissipates as it travels.
*Can be stimulated by neurotransmitter binding to ligand-gated channels, mechanical stress, or temperature change.
Graded potential
The six-step for how information is transmitted through the nervous system
______- Electrical impulse producing a brief reversal of the membrane potential that travels down the entire length of the axon from the axon hillock to the axon terminals.
*Rising (depolarization) phase of the action potential
*Falling (Repolarization) phase of the action potential
Action potential
Action potential
________; Na+ rushes in through volatage gated Na+ channels
*Threshold potential: V-gate Na+ channels open at membrane potential of -55 mV
Rising (depolarization) phase of the action potential.
Action potential
______: K+ rushes out through voltage gate K+ channels
Falling ( Repolarization) phase of the action potential
What are the structure and functions of the synapse?
Function:
Synapse
Structure: Presynaptic neuron -Axon Terminals Synaptic cleft Post synaptic cell (neuron, muscle, gland, ect).
What is the function of the synapse?
_____- the junction between two neurons or a neuron and muscles
Synapse
What are the structure and functions of the synapse?
______- transmits impulse towards the synapse.
* Axon terminals of the presynaptic neuron release neurotransmitters
Presynaptic neuron
______- Fluid-filled space where neurotransmitter is released
Synaptic cleft
______- receives information from the presynaptic neurons.
Postsynaptic cell ( neuron, muscle, gland, ect)
