Test 3 (Final) Flashcards
This deck was created by combining two or more decks
Parasympathetic NS
Rest and digest
Vegetative functions
Decrease HR, decrease BP, increase digestive function
Conserves energy
Almost all viscera is innervated by ________ the parasympathetic and the sympathetic systems
Both
Myelin
Fatty protien that coats the axon
Functions to speed the conduction of the APs
Gaps between the myelin are called nodes of panvier
The AP jumps from node to node via saltatory conduction
Axon
Conducting zone
Conducts/propagates the APs
Peripheral nervous system (PNS)
All neural tissue outside of the CNS
Consists of cranial nerves and spinal nerves
Sensory and motor
Soma
Cell body of a neuron
Contains the nucleus and all other organelles
CNS= nuclei
PNS= ganglia
Somatic NS
System of motor neurons that conduct AP from CNS to skeletal muscle
Dendrites
Input zone
Receive signals
Axon hillock
Trigger zone
Sums incoming signals (inhibitory and excitatory)
Generates AP if threshold is reached
Sensory/afferent system
Carries signals from sensory receptors to CNS (input)
Central nervous system (CNS)
Brain and spinal cord
Command center that receives information form sensory receptors
Propogate
To reproduce and spread
Axonal/terminal branches
Carry the AP to several extensions
The AP remains the same strength in all the branches
Sympathetic NS
Fight or flight
Energetic functions
Increase HR, increase BP, decrease digestive function
Autonomic NS
Visceral nerve fibers that conduct AP from CNS to smooth muscle, cardiac muscle, and glands
Parasympathetic and sympathetic
Neurons/nerve cells
Highly specialized to conduct APs throughout the body
Lose the ability to divide and reproduce at maturity (have extreme longevity)
Very high metabolic rate therefore they need a constant supply of oxygen and glucose to prevent irreversible damage
Axon terminals
Secretory zone
Release of neurotransmitters/neurohormones to communicate with another neuron, muscle, or gland
Motor/efferent
Carries signals from the CNS to effector organs
Results in the contraction of muscle or glandular secretion
Somatic NS and autonomic NS
Anticholinergics
Ah receptor antagonist
Ex. Atropine
Curare
Curare
N2 receptor antagonist
Decrease in skeletal muscle activity
Best know for its uses as an arrow poison in south America
Drug causes paralysis
Neostigmine
Used to treat myasthenia gravis
Autoimmune disease where N2 receptors on skeletal tissue are destroyed
Drug allows Ach to increase stimulation of functioning N2 receptors
Antiadrenergics
Adrenergic receptor antagonists
Blocks sympathetic response
Ex. Propranolol
Hytin
Physostigmine
Used to treat digestive disorders that result in a decrease in gut motility
Increase gut activity (M3)
Propranolol
Beta1 receptor blocker
Treatment for high blood pressure
Drug causes a decrease I’m HR, which leads o a decrease in BP
Parasympathomimetics
Muscarinic receptor agonists
Similar in structure to Ach
Cause parasympathetic response
Ex. Pilocarpine
Ach-esterase inhibitors
Pent the breakdown of Ach allowing it to exert its effects for a longer period of time
Ex. Physostigmine
Neostigmine
Agonist
Binds to a receptor and elicits a response
Pilocarpine
Used to treat glaucoma
Condition caused by The compression of the optic nerve by excess fluid
Drug induces contraction of the muscle in the eye (ciliary) which aids the fluid drainage (M3)
Atropine
Muscarinic receptor blocker
Blocks the parasympathetic response
Used to reduce salivation Nd mucus production in surgical patients
Drug decreases glandular secretory activity (M3)
Hytin
Alpha1 receptor blocker
Treatment for tissue hypoxia
Drug causes vasodilation of blood vessels, increase blood flow
Sympathomimetics
Adnergic receptor agonists
Similar in structure to epinephrine and neuroepinephrine
Elicit a sympathetic response
Ex. Ventolin
Antagonist
Binds to a receptor and blocks a response
Ventolin
Used as a treatment for asthma
Drug causes relaxation of smooth muscle surrounding the bronchioles (Beta2)
Postsynaptic cell
The receiving structure
Each AP is _______, APs _______ decrease on intensity during propagation
Identical
Do not
Neuro- neuronal synapse
One neuron to another neuron
Chemical synapses
Much more common
Specialized for the release and reception of neurotransmitters and neurohormones
Convert electrical signals into chemical signals
Neuro-glandular synapse
One neuron to a gland
Chemical synapse
Convert electrical to chemical
The chemical signal travels across the synapse to the post synaptic structure
And then is converted back into electrical signals
Neuro- muscular synapse
One neuron to a muscle
Functional types of synapses
Electrical
Chemical
During repolarization the membrane is in
A relative refractory period
The post synaptic structure can be……..
Excited or inhibited
Excitatory post synaptic potential
NT/NH binding causes channels that allow depolarization to open
Becomes more positive on the inside
Brought closer to threshold
Usually chemically gated Na+ ion channels (influx)
As the AP travels down the length of the axon
It is newly generated at each patch of the membrane
Gap junctions
Specialized cellular adhesions
Relative refractory period
A 2nd AP can be generated on top of the first if the stimulus is strong enough
Inhibitory post synaptic potential
NT/NH binding causes channels that induce hyperpolarization to open
Becomes more negative on he inside
Taken further from threshold
Can be chemically gated K+ ion channels (eflux) or chemically gated Cl- ion channels (influx)