Nerve Physio Flashcards by Adrian Gamo

Main genetic and metabolic center of the neuron.

Cell body/ Soma

How well did you know this?

Not at all

Perfectly

Contains the nucleus and nucleolus of the cell

Cell body/ soma

How well did you know this?

Not at all

Perfectly

Also a region in which the neuron receives synaptic input

Cell body/ soma

How well did you know this?

Not at all

Perfectly

The rough ER, called Nissl substance, and neurofibrils are abundant

Cell body/soma

How well did you know this?

Not at all

Perfectly

The main direct recipients of signals from other neurons

Dendrites

How well did you know this?

Not at all

Perfectly

Conduct nerve impulse toward the cell body

Dendrites

How well did you know this?

Not at all

Perfectly

Longest process in the body

Axon

How well did you know this?

Not at all

Perfectly

Longest process in the body

Axon

How well did you know this?

Not at all

Perfectly

The initial segment is usually the site where action potentials (spikes) that are propagated down the axon are initiated

Axon Hillock

How well did you know this?

Not at all

Perfectly

Most excitable part

Axon Hillock

How well did you know this?

Not at all

Perfectly

Whitish fatty material

Myelin sheath

How well did you know this?

Not at all

Perfectly

Protects and insulates the fibers and increases the transmission rate of nerve impulses

Myelin sheat

How well did you know this?

Not at all

Perfectly

facilitate faster impulse conduction, oligodendrocytes and schwann cells

Myelin sheats

How well did you know this?

Not at all

Perfectly

where ions still can flow with ease through the axon mem-
brane between the extracellular fluid and intracellular fluid
inside the axon. This area is called the

Nodes of ranvier

How well did you know this?

Not at all

Perfectly

where ions still can flow with ease through the axon mem-
brane between the extracellular fluid and intracellular fluid
inside the axon. This area is called the

Nodes of ranvier

How well did you know this?

Not at all

Perfectly

contains membranous sacs that contain chemicals called neurotransmitters

Axon terminal

How well did you know this?

Not at all

Perfectly

where multiple local potential changes generated by synaptic connections are integrated

Receptor or dendritic zone

How well did you know this?

Not at all

Perfectly

where action potentials cause the release of synaptic transmitters

Nerve endings

How well did you know this?

Not at all

Perfectly

that transmits propagated impulses to the nerve endings

Axonal process

How well did you know this?

Not at all

Perfectly

carrying impulses from the sensory receptors

Sensory afferent

How well did you know this?

Not at all

Perfectly

detect amount of stretch or tension, in skeletal muscles, their tendons and joints

Proprioreceptors

How well did you know this?

Not at all

Perfectly

neurons carrying impulses from the CNS to the viscera or muscles

Efferent neurons

How well did you know this?

Not at all

Perfectly

connect the motor and sensory neurons in neural pathways

Interneurons or association neurons

How well did you know this?

Not at all

Perfectly

• Several neurons
• Most common type

Multipolar neuron

How well did you know this?

Not at all

Perfectly

Two processes, an axon and a dendrite; rare in adults (eye, nose)

Bipolar neuron

• Axons conduct nerve impulses both toward and away from the cell body (sensory neurons in the PNS)

Unipolar neuron

• Single process emerging from the cell body

Unipolar neuron

*Most synapses occur on * In the cerebral and cerebellar cortex, endings are commonly located on

Axodendritic

but some presynaptic nerves terminate on the

Axosomatic synapse

is a specialized type of synapse where one neuron's axon terminal forms a connection with another neuron's axon

Axoaxonic

is a junction between the axon terminal of one neuron and the dendrite of another neuron

Axodendritic

is a junction between the axon terminal of one neuron and the soma (cell body) of another neuron.

Axosomatic

Wheretwoneuronscomeinto close proximity and functional interneuronal communication occurs

Synapses

Communication at a _______, under physiologic conditions, takes place in one direction only

Synapse

the neurotransmitter, passes across the narrow space between the cells and becomes attached to a protein molecule in the postsynaptic membrane called _____

Receptor

The vesicles fuse with the ___________and discharge the neurotransmitter(s) into the _________ by a process of exocytosis

Presynaptic membrane, synaptic cleft

containing channels that extend from the cytoplasm of the presynaptic neuron to that of the postsynaptic neuron

Gap junctions

Rare in the human central nervous system

Electrical synapse

Gap junctions containing channels that extend from the cytoplasm of the presynaptic neuron to that of the postsynaptic neuron

Electrical synapse

The bridging channels permit ionic current flow to take place from one cell to the other with a minimum of delay.

Electrical synapse

In ________ ,the rapid spread of activity from one neuron to another ensures that a group of neurons performing an identical function act together.

Electrical synapse

___________ also have the advantage that they are bidirectional; ____________ are not.

Electrical synapses, chemical synapses

release of neurotransmitter substances at synapses

Presynaptic vesicles and mitochondria

Most ______ produce and release only one principal transmitter at all their nerve endings.

Neurons

is widely used as a transmitter by different neurons in the central and peripheral parts of the nervous system

Acetylcholine

Star-shaped cells that account for nearly half of the neural tissue.

Astrocytes

Their numerous projections have swollen ends that cling to neuron, bracing them and anchoring them to their nutrient supply lines, the blood capillaries.

Astrocytes

Form a living barrier between capillaries and neurons and play a role in making exchanges between the two.

Astrocytes

spider-like phagocytes that dispose debris, including dead brain cells and bacteria

Microglia

line the central cavities of the brain and SC

Ependymal cells

The beating of their cilia helps to circulate the Cerebrospinal fluid (CSF) that fills those cavities and forms a cushion around the CNS.

Ependymal cells

Glia that wrap their flat extensions tightly around the nerve fibers,

Oligodendrocytes

producing fatty insulating coverings called

Myelin sheats

are transmitted by ACTION POTENTIAL GENERATION action potentials, which are rapid changes in the membrane potential that spread rapidly along the nerve fiber membrane

Nerve signals

Each action potential begins with a sudden change from the normal resting _______ membrane potential to a _______ potential and then ends with an almost equally rapid change back to the ________potential

Negative,positive,negative again

membrane potential is at -70mV

Resting stage

membrane suddenly becomes permeable to sodium ions, allowing tremendous numbers of positively charged sodium ions to diffuse to the interior of the axon. (40 mV)

Depolarization stage

The normal "polarized" state of_________ is immediately neutralized by the inflowing positively charged sodium ions, with the potential rising rapidly in the positive direction

-90 millivolts

The sodium channels begin to close and the potassium channels open more than normal.

Repolarization stage

rapid diffusion of ______ to the exterior re-establishes the normal negative resting membrane potential

Potassium ions

Different types of _______excite ________ to become active and generate impulse

Stimuli,neurons

Most neurons in the body are excited by

Neurotransmitters

Normally, _________cannot diffuse through the plasma membrane, but when the neuron is stimulated, the “gates” of sodium channels in the membrane open

Sodium ions

Higher to lower concentration what law is this

Law of diffusion on sodium

Duration of non-excitable state

REFRACTORY PERIOD

Controls the maximum frequency that the action potentials can be conducted along the plasma membrane

REFRACTORY PERIOD

________ in myelinated axons jumps from one node of Ranvier to the next

Depolarization

In the__________ state, the gates of the _________ are ________ than those of the sodium channels, which are nearly closed.

Nonstimulated, potassium channels, open wider

In the ________state, the gates of the sodium channels are at first _________ ; then, the gates of the ________ are opened, and the gates of the sodium channels are nearly closed again.

Stimulated channels, open wider, potassium channels

It is the opening and closing of the sodium and potassium channels that is thought to produce the _______ and_________ of the plasma membrane.

Depolarization and repolarization

occurs at the onset of the action potential when a second stimulus is unable to produce a further electrical change. It is thought to be due to the inability to get the sodium channels open

Absolute refractory period

when a very strong stimulus can produce an action potential, presumably the sodium channels are opened.

Relative refractory period

Anautoimmunediseasethataffectsover3 million people worldwide, usually striking be- tween the ages of 20 and 50 and affecting women about twice as often as men.

Multiple sclerosis

The cause of ______appears to include both genetic and environmental factors.

Multiple sclerosis

_________,antibodiesandwhitebloodcellsinthe immune system attack myelin, causing inflammation and injury to the sheath and eventually the nerves that it surrounds.

Multiple schlerosis

Loss of ____leads to leakage of ____through voltage- gated channels, hyperpolarization, and failure to conduct action potentials

Myelin, k+