Stimulus cause threshold potential to be -55 mV Voltage-gated Na channels open, Na+ diffuses into cell Inside develops a positive charge K+ channels close

Depolarization to repolarization Na+ reaches peak and channels close

Na+ channels close Voltage gated K+ channels open, K+ diffuses out Inside of cell becomes negative once again Absolute refractory period

Inside of cell becomes more negative than resting potential due to K+ flow Relative refractory period

1. AP reaches end of presynaptic axon  voltage gated Ca++ channels open and enters neuron 2. Ca++ cause synaptic vesicles to fuse/exocytosis from neuron with NT inside 3. NT binds to ligand gated ion channels on post synaptic neuron  graded potentials 4. Graded potentials summate at axon hillock and AP fires once it passes threshold

Nervous System Flashcards by Anneli Rios

neuronal

cellular communication

fast, direct, targets specific cells/tissues (nerves)

How well did you know this?

Not at all

Perfectly

hormonal

cellular communication

seen in the endocrine system
slow
widespread
affects multiple cells/tissues throughout body

How well did you know this?

Not at all

Perfectly

paracrine system

cellular communication

local hormones released by cells into IF to act on a nearby cell

How well did you know this?

Not at all

Perfectly

neuron structure

soma, dendrites, and axons

How well did you know this?

Not at all

Perfectly

neuron function

transmit electrical signals from one cell to another

How well did you know this?

Not at all

Perfectly

soma

cell body

How well did you know this?

Not at all

Perfectly

dendrites

extension –> receives signals signal

How well did you know this?

Not at all

Perfectly

axon

sends signal out
* axon hillock
* myelin sheath
* nodes of ranvier

How well did you know this?

Not at all

Perfectly

axon hillock

axon

connection to cell body

How well did you know this?

Not at all

Perfectly

myelin sheath

axon

fatty acid insulation (speed up AP by stopping ion exchange)

How well did you know this?

Not at all

Perfectly

cells that make myelin

axon

oligodendrocytes in CNS
schwann cells in PNS

How well did you know this?

Not at all

Perfectly

white matter

axons with myelin

How well did you know this?

Not at all

Perfectly

gray matter

axons without myelin

How well did you know this?

Not at all

Perfectly

Resting membrane potential

70 mV
Establish by Na+/K+ pump
3 Na+ out, 2 K+ in makes inside of cell have negative charge relative to outside
Maintained by Na+/K+ ATPases via hydrolysis of ATP
K+ leaky channels also maintain RMP

How well did you know this?

Not at all

Perfectly

Depolarization

Stimulus cause threshold potential to be -55 mV
Voltage-gated Na channels open, Na+ diffuses into cell
Inside develops a positive charge
K+ channels close

How well did you know this?

Not at all

Perfectly

Transition point

Depolarization to repolarization
Na+ reaches peak and channels close

How well did you know this?

Not at all

Perfectly

Repolarization

Na+ channels close
Voltage gated K+ channels open, K+ diffuses out
Inside of cell becomes negative once again
Absolute refractory period

How well did you know this?

Not at all

Perfectly

Hyperpolarization

Inside of cell becomes more negative than resting potential due to K+ flow
Relative refractory period

How well did you know this?

Not at all

Perfectly

Absolute refractory period

no stimulus can cause AP
* Due to inactivation of Na+ channels

How well did you know this?

Not at all

Perfectly

Relative refractory period

requires strong stimulus for AP

How well did you know this?

Not at all

Perfectly

Synapse

AP reaches end of presynaptic axon  voltage gated Ca++ channels open and enters neuron
Ca++ cause synaptic vesicles to fuse/exocytosis from neuron with NT inside
NT binds to ligand gated ion channels on post synaptic neuron  graded potentials
Graded potentials summate at axon hillock and AP fires once it passes threshold

How well did you know this?

Not at all

Perfectly

EPSP (excitatory postsynaptic potential)

depolarized membrane and cause Na+ ions to flow into cell

How well did you know this?

Not at all

Perfectly

IPSP (inhibitory postsynaptic potential)

hyperpolarized membrane and causes K+ to flow OUT and Cl- in

How well did you know this?

Not at all

Perfectly

Electrical synapse

Study These Flashcards

in cardiac/smooth muscle cells
* Gap junctions allow electrical signal to go through much faster than chemical synapse

Chemical synapse

NT released into synaptic cleft diffuses to receptors on next cell * Second messenger system: G protein connected to receptor activated when NT binds, can open channels, activate proteins or cause gene transcription * can only happen in 1D, slowest part

sensory/afferent

carries signals from receptors to brain via interneurons

interneurons

carries signal from neuron to neuron

motor/efferent

carries signals from brain to muscle/glands

glia cells

* non-neuronal cells in nervous system * support and surround neurons

microglial cells

macrophages that protect CNS

macroglial cells

* **astrocytes**: from blood brain barrier, recycle NT, provide blood to CNS * **satellite cells**: astrocytes of PNS * **schwann cells**: myelin sheath in PNS * **oligodendrocytes**: myelin sheath in CNS * **ependymal cells**: produce CSF in CNS

amino acid NT

* glutamate: excitatory * GABA and glycine: inhibitory

amino acid derived NT

* **Epi/NE**: excitatory @ postsynaptic neuron * **dopamine**: excitatory in brain (reward-motivated) * **serotonin**: inhibitory in brain (mood, sleep) and increases contraction in GI

gas NT

NO --> vasodilation

other NT

ACh * excitatory @ presynatpic neurons * excitatory @ muscles * post-synaptic NT in PNS

CNS

brain + spinal cord

higher brain

cerebrum, cerebral cortex * conscious activties like memories and thoughts

lower brain

medulla, hypothalamus, thalamus, cerebellum * subconscious activies like breathing, BP, emotions, reactions to pains

meninges

protect CNS and have 3 layers * **DAP**: dura mater, arachnoid mater, pia mater

frontal lobe

high function processes * decision making, problem solving, attention, and concentration

temporal lobe

speech and hearing

occipital lobe

vision

parietal lobe

spatial perception (PAT) and sensation

cerebellum

mini brain underneath occipital lobe, import for coordination of movement

brainstem

midbrain, pons, medulla oblongata

midbrain

relays sensory information

pons

relays messages between forebrain and medulla

medulla oblongata

HR, breathing rate, BP, toxic sensing

limibic system

emotions, memory, learning, and motivation * thalamus, hypothalamus, hippocampus, amygdala

thalamus

relays sensory and motor information

hypothalamus

regulates hormone secretion in body

hippocampus

responsible for memory consolidation

amydala

emotional reactions happen here to scents

PNS

* everything else (all nerves branching off CNS) * CNS * ANS * recieves input from sensory (afferent) neurons

somatic nervous system (SNS)

voluntary sensor and motor functions, responds to environment * controls skeletal muscle, use ACh

autonomic nervous sytem

involuntary controls smooth muscle, cardiac muscle * sympathetic and parasympathetic ANS

sympathetic ANS

* "fight or flight", increases HR, increases blood flow to skeletal msucles, decreases blood flow to digestive system * Epi/NE * releases sugar into blood for energy * increase HR for oxygen delivery * vasodilation of skeletal blood vessels * vasoconstriction of GI system * dilation of bronchi and bronchioles to allow O2 to lungs * dilates pupils to increase information to the brain

parasympathetic ANS

* "rest and digest", opposite of sympathetic * ACh * SLUDGE (salivation, lacrimation, urination, defamation, GI, excretion) * relaxes muscles * decrease HR * maintains homeostasis

Nervous System Flashcards

(58 cards)