Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
60 Cards in this Set
- Front
- Back
transducers
|
converts one kind of stimulation to another
|
|
Conductors
|
Transmits info from A to B
|
|
Integrators
|
Impulses will be interpreted
|
|
cells found in Nervous System
|
Neurons & Glial Cells
|
|
Kinds of neurons
|
1. Anaxonic
2. Bi-Polar 3. Unipolar 4. Multipolar |
|
Anaxonic Neuron
|
- not well understood
- connecting neurons in the CNS - no axon |
|
Bi-Polar Neuron
|
- 1 axon
- 1 dendrite - sensory (special senses - taste, vision) |
|
Unipolar Neuron
|
- sensory (hot, cold, touch)
- axon a little shorter than dendrite - Ex. Dorsal Root Ganglion |
|
Multipolar Neuron
|
- motor neuron
- connecting neurons - peripherial nervous system |
|
Types of Glial Cells (Neuroglia)
|
Of CNS:
1. Ependymal 2. Astrocytes 3. Microglia 4. Oligodendrocytes Of PNS: 1. Satellite cells 2. Schwann Cells |
|
2 glial cells that work together to form BBBarrier
|
Ependymal and Astrocytes
|
|
Ependymal cells
|
In CNS:
- behave as epithelial - lines and covers tissues |
|
Astrocytes
|
In CNS:
- multi processes - connective tissue of CNS - structural support - work with Ependymal cells for BBB |
|
Microglia cells
|
In CNS:
- wandering phagocytes of CNS - ingest potential pathogens - clean up debris |
|
Oligodendrocytes
|
In CNS:
- myelination of fibers in CNS |
|
Satellite Cells
|
In PNS - similar to Epindymal and Astrocytes
|
|
Schwann Cells (aka neurolemmacyte)
|
In PNS:
- surround axons in PNS - myelination in PNS |
|
Nerve
|
Bundle of axons and/or dendrites.
|
|
Membrane potential
|
Difference in charge between inside and outside of cell.
|
|
All membranes have 3 types of ion channels
|
1. leak channels
2. Sodium Potassium Exchange pump 3. Gated - chemical, mechanical, voltage |
|
Leak channels
|
- aka passive channels
- always open - tend to be more permeable to K than Na |
|
3 forms of gated channels
|
- chemically regulated
- voltage-regulated - mechanically regulated |
|
3 states of gated channels
|
- closed, but capable of opening
- open - closed, incapable of opening |
|
Sodium Potassium Exchange Pump
|
- maintains resting potential at -70mV
- used ATP to pump out Na+ and pump in K+ 3 Na to 2 K |
|
What initiates an action potential?
|
Opening and closing of gated channels.
|
|
Action Potentials
|
Propagated changes in the transmembrane potential that, once initiated, affect an entire excitable membrane.
|
|
Absolute refractory period
|
Does not matter how many other stimuli, cannot get another action potential.
|
|
Relative refractory peoriod
|
possible to get another action potential generated, but takes greater stimuli
|
|
summation
|
addition of stimuli
|
|
temporal summation
|
addition of stimuli occurring in rapid succession.
Occurs at a single synapse |
|
spatial summation
|
simultaneous stimuli at different locations have a cumulative effect on the transmembrane potential.
|
|
EPSP creates?
|
Excitatory Post synaptic potential
- depolarization (move toward threshhold) |
|
IPSP creates?
|
Inhibitory Post Synaptic Potential
- hyperpolarize - move away from threshold. |
|
Saltatory conduction (propagation)
|
Action potential "jumps" from node to node rather than moving along the axon in a series of tiny steps.
|
|
3 types of fibers & describe
|
Type A - largest, myelinated, 300 mph
Type B - intermediate, myelinated, 40-45 mph Type C - smallest, unmyelinated, continuous propagation, 2 mph |
|
2 forms of synapses
|
Electric or Chemical
|
|
Electric synapse
|
- rarest
- the pre & post synaptic membranes are locked together at gap junctions - known advantage - quicker response due to connection at gap junctions. |
|
2 types of Chemical synapse & describe
|
- may or may not propagate the postsynaptic cell - depends on the NT
Cholinergic - synapses that release AcH Adrenergic - uses a variety of NT |
|
Neuromodulators
|
- not necessarily a NT
- alters the rate of release of NT or alters the affect the NT has on the post synaptic membrane. - can effect pre,post or both at the same time - can operate on thei own or in conj with NT's. |
|
NM effects
|
Direct effect - Ionotropic - causes change in ion concentrations between inside and outside of receptor cells.
Indirect effect - Metabotropic - causes metabolic ahnges of the post synaptic cell. Overall change in the cells metabolism. G-protein GTP enzymes linked to them. |
|
What affects nerve inpulses?
|
concentration of Na+, K+, Ca+, Temperature
if conc of Na+ & K+ are to high or low, affect resting potential, if temp high, ion movement faster through leak channels. H+ in extracellular fluid - effect of depolarizing membrane Buffers very important in cellular physiology |
|
Types of reflexes
|
- learned/acquired - trained response
- somatic - control skeletal muscle contractions - visceral - autonomic - cardiac muscle - monosynaptic - one synapse - polysynaptic - more than one synapse - cranial - processing in brain - spinal - processing in the spinal cord |
|
4 types of neural pathways
|
- Linear pathway (serial processing)
- Diverging pathway (one -- to many) comon - motor - Converging pathway (many -- to one) common - sensory - less convergence - Reverberating (Linear -- loop) will continue to cycle stimulate until circuit fatigues or run out of NT's |
|
5 sensory receptors
|
1. thermoreceptors (free nerve endings)
2. chemoreceptors (respond to chemical changes) 3. photoreceptors (respond to light) 4. mechanoreceptors (respond to mechanicl stimulus) 5. nociceptors (pain receptors) |
|
break down Mechanoreceptors
|
1. baroreceptor - blood pressure
2. tactile receptors - touch receptors a. tactile disc (merkels discs) free nerve endings with padlike structures. b. lamellated corpuscle (deep touch - vibratory receptors) c. organ of ruffini (deep touch - do not adapt quickly) |
|
Site of sharpest vision
|
fovea
|
|
Blind spot?
|
Optic disc
|
|
Rods
|
react to all wave lengths of visible, low intensity light.
|
|
Cones
|
respond to certain wavelengths - color vision.
|
|
Organ of Corti
|
organ of hearing
|
|
amplitude
|
how many hair cels are being stimulated at a given time.
|
|
dynamic equilibrium
|
semi circular ducts filled with endolymph
detect rotational movements of the head. |
|
static equilibrium
|
Utricle and Saccule
Provide equilibrium sensations, whether the body is moving or is stationary. |
|
incomplete tetany
|
muscle fiber contract, begin to relax but restimulated
|
|
complete tetany
|
stimulation so close together - no chance to relax. muscle will fatigue.
|
|
treppe
|
tension rises in stages - like warming up
|
|
types of muscle contractions
|
Isotonic - as muscle contracts - tension remains stable - muscle gets shorter. (to move)
Isometric - as muscle contracts - tension increases - muscle does not change much (maintaining posture) |
|
Kinds of muscle fibers
|
1. slow twitch (lg # of mitochondria, high conc of myoglobin, slower to react, slower to fatigue)
2. intermediate (middle # of mitoch & myoglobin,) 3. fast twitch (few mitochondria, myoglobin, anerobic resp, react quick, fatigue rapidly) |
|
Charactics of Cardiac muscle
|
- intercallated discs (gap junctions between cells)
- striated, pacemaker cells, - deep nuclei |
|
2 subgroups of smooth muscle
|
single unit & multi unit
|