Question | Answer |
Neuron with resting membrane potential more negative... | Inhibited or hyperpolarized |
Myelinated Neurons | greater conduction velocity |
Parasypathetic nervous system activates what receptors in effector organs? | Muscarinic Receptors |
What is the most common neurotransmitter released from parasympathetic postganglionic fibers? | Acetylcholine |
What receptor is found at the synapse between preganglionic and postganglionic neurons of the sympathetic and parasympathetic nervous system? | Nicotinic Receptors |
What type of effect can acetylcholine have? | Inhibitory or excitatory depending on the type of receptor activated |
What is a rapid, but transient change in membrane potential? | Action potential |
What type of channels do action potentials require? | Sodium and potassium voltage-gated ion channels. |
Where do sodium and potassium voltage-gated ion channels occur? | At regions of the cell membrane that are electrically excitable. |
What is threshold? | The point at which voltage-gated channels will open. |
Graded response is... | subthreshold response |
Examples of a graded response. | receptor (generator) potentials, pacemaker potentials, postsynaptic membrane potentials, end-plate potentials |
When a graded potential reaches threshold... | action potential is generated. |
Variable changes in magnitude of the potential... | graded potential |
Decrease in magnitude as they move along the cell membrane but can function as signals over a very short distance... | graded potential |
Graded potential caused by a stimulus... | receptor potential |
Sensory receptors respond to stimuli from... | Mechanoreceptors, thermoreceptors, nociceptors (pain), chemoreceptors, electromagnetic (vision) receptors. |
What is the pathway of a graded potential? | graded potential--> Threshold--> Action Potential generated--> Sensory input transmitted to spinal cord and brain. |
Why are action potentials propagated with out degradation? | It is constantly regenerated all along the membrane. |
What organ recieves preganglionic sympathetic fibers? | Medulla of the adrenal glands. |
What do chromaffin cells of the medulla of the adrenal glands secrete? | catecholamines |
What are catecholamines? | Norepinephrine and epinephrine |
What part of the brain is involved in the arousal from a deep sleep? | Reticular Formation |
What is the reticular formation responsible for? | regulating periods of unconsciousness and consciousness. |
What is the collection of nerve endings around a hair follicle that allows for sensation of the hair being touched called? | Peritricial Plexus |
What neurotransmitter is associated with the motor end-plate? | Acetylcholine |
Motor end-plate is associated with? | Skeletal muscles |
What is the neurotransmitter in the basal ganglion? | dopamine |
What is the condition of impaired neurotransmitter reception at the motor end-plate | Myasthenia Gravis |
Responsible for carrying vibration sense, proprioception and complex touch to the upper extremity? | Fasciculus Cuneatus |
Motor Tract from the cerebellu | |
Neuron with resting membrane potential more negative... | Inhibited or hyperpolarized |
Myelinated Neurons | greater conduction velocity |
Parasypathetic nervous system activates what receptors in effector organs? | Muscarinic Receptors |
What is the most common neurotransmitter released from parasympathetic postganglionic fibers? | Acetylcholine |
What receptor is found at the synapse between preganglionic and postganglionic neurons of the sympathetic and parasympathetic nervous system? | Nicotinic Receptors |
What type of effect can acetylcholine have? | Inhibitory or excitatory depending on the type of receptor activated |
What is a rapid, but transient change in membrane potential? | Action potential |
What type of channels do action potentials require? | Sodium and potassium voltage-gated ion channels. |
Where do sodium and potassium voltage-gated ion channels occur? | At regions of the cell membrane that are electrically excitable. |
What is threshold? | The point at which voltage-gated channels will open. |
Graded response is... | subthreshold response |
Examples of a graded response. | receptor (generator) potentials, pacemaker potentials, postsynaptic membrane potentials, end-plate potentials |
When a graded potential reaches threshold... | action potential is generated. |
Variable changes in magnitude of the potential... | graded potential |
Decrease in magnitude as they move along the cell membrane but can function as signals over a very short distance... | graded potential |
Graded potential caused by a stimulus... | receptor potential |
Sensory receptors respond to stimuli from... | Mechanoreceptors, thermoreceptors, nociceptors (pain), chemoreceptors, electromagnetic (vision) receptors. |
What is the pathway of a graded potential? | graded potential--> Threshold--> Action Potential generated--> Sensory input transmitted to spinal cord and brain. |
Why are action potentials propagated with out degradation? | It is constantly regenerated all along the membrane. |
What organ recieves preganglionic sympathetic fibers? | Medulla of the adrenal glands. |
What do chromaffin cells of the medulla of the adrenal glands secrete? | catecholamines |
What are catecholamines? | Norepinephrine and epinephrine |
What part of the brain is involved in the arousal from a deep sleep? | Reticular Formation |
What is the reticular formation responsible for? | regulating periods of unconsciousness and consciousness. |
What is the collection of nerve endings around a hair follicle that allows for sensation of the hair being touched called? | Peritricial Plexus |
What neurotransmitter is associated with the motor end-plate? | Acetylcholine |
Motor end-plate is associated with? | Skeletal muscles |
What is the neurotransmitter in the basal ganglion? | dopamine |
What is the condition of impaired neurotransmitter reception at the motor end-plate | Myasthenia Gravis |
Responsible for carrying vibration sense, proprioception and complex touch to the upper extremity? | Fasciculus Cuneatus |
Motor Tract from the cerebellum? | rubrospinal tract |
Responsible for carrying vibration, proprioception and complex touch for the lower extremity? | Fasciculus Gracilus |
Carries pain and temperature? | anterior spinothalamic tract |
Increased permeability to chloride causes an influx of cholride into the cell resulting in... | hyperpolarization |
Mydriasis, pupil dialation is what type of autonomic response? | sympathetic |
Peristalsis, erection and salivation are what type of autonomic response? | parasympathetic |
Rapid influx of sodium ions into a cell that is physiologically excitable? | depolarization |
Two types of depolarization. | Action potential and EPSP (excitatory postsynaptic potential) |
Occurs only if threshold is achieved? | action potential |
Associated with influx of chloride ions or efflux of potassium ions? | hyperpolarization |
Characterized by reduced sodium permeablility | refractory period |
sodium influx | depolarization |
potassium efflux | repolarization or hyperpolarization |
calcium influx | release of neurotransmitter vesicles from the terminal bouton of the axon |
Resting membrane potential | membrane is polarized |
neurotransmitter responsible for the conversion of chemical energy into bioelectrical energy at the motor end plate of skeletal muscle? | acetylcholine |
neurotransmitter of autonomic nervous system | norepinephrine |
serve as neurotransmitters in the CNS | GABA and Histamine |
refers to peak voltage of an action potential | amplitude |
Myelination and fiber diameter increase? | speed of propagation |
Governed by the concentration of intracellular and extracellular ions | Amplitude |
What causes the repolarization phase of an action potential? | influence of potassium channels |
Inhibitory neurotransmitter of the CNS | GABA (gamma-aminobutyric acid) |
Excitatory Neurotransmitters | Epinephrine, Glutamate, Norepinephrine |
What do drugs that block a voltage-gated Na channel in nerves do? | Won't allow action potential to occur |
What is necessary for depolarization to happen? | opening of voltage-gated sodium channels |
Nernst potential for sodium | positive |
Nernst potential for potassium | negative |
By preventing sodium entry in cell membrane, no additional action potentials can occur. What is this phase called? | Absolute refractory period |
Housekeeping cells of the CNS | microglial cells |
Due to effects of a single synapse firing a rapid succession... | temporal summation |
Neuron with resting membrane potential that is more negative... | inhibited or hyperpolarized |
myelinated neurons | greater conduction velocity |