What are the functions of smooth muscle?
produce motility, maintain tension
What are the two classifications of smooth muscle, based on electrical stimulus?
Which type of smooth muscle has gap junctions?
Gap junctions allow ________ _______ between cells, which permits quick spread of action potentials simultaneously.
What type of smooth muscle is found in the bladder?
Which type of smooth muscle posesses spontaneous pacemaker activity?
Hypoxia in the blood vessels causes _________ (and thus relaxation of the smooth muscle)
Vasodilation is increased by what?
excess CO2-, K+, increased lactic acid, increased temperature, decreased Ca2+
What are the two types of unitary smooth muscles?
Where is phasic smooth muscle found?
Where is tonic smooth muscle found?
Phasic smooth muscle shows ________ contractions.
Tonic smooth muscle shows ______ contractions.
Phasic smooth muscle shows what type of action potential?
Tonic smooth muscle shows what type of action potential?
none- electrically inexcitable
What are some examples of mutiunit smooth muscle?
iris, ciliary muscles, vas deferens
Is there couple between the cells of multiunit smooth muscle? How about unitary smooth muscle?
The thick filaments of smooth muscle contain ______, and the thin filaments are composed of ______ and ________ only.
myosin, actin, tropomyosin
What contractile protein found in skeletal muscle is NOT found in smooth muscle?
What structure is found in skeletal muscle but not in smooth? What structure is less developed in smooth muscle?
What are T tubules replaced with in Smooth muscle fibers
In both unitary and multiunit muscle cells, motor nerve fibers contain bulges called _______.
In smooth muscle fibers, As action potential sweeps down the motonerve, neurotransmitter is released from synaptic vesicles stored where?
Through what channels can Ca enter the cell in smooth muscle AP?
voltage-gated Ca2+, ligand-gated channels, IP3-gated Ca2+
What opens voltage-gated Ca2+ channels in smooth muscle?
depolorization of action potential
What opens ligand-gated channels and IP2 gated channels in smooth muscle?
hormones and neurotransmitters
In smooth muscle AP, a rise in intracellular Ca2+ concentration prompts binding of Ca2+ to what protein?
How many calcium ions can calmodulin bind?
The Ca2+ calmodulin complex not only binds to ____________, but also activates it.
What binds to actin to form cross-bridges in muscular contraction?
How much ATP is used for each cross-bridge cycle is smooth muscle contraction?
What mechanism allows myosin to remain attached to actin for sometime without expending more energy?
What causes relaxation of smooth muscle fibers?
SR re-accumulates Ca2+ via the Ca2+ ATPase
Cycling of cross-bridges in smooth muscle is ______ and in skeletal muscle it is _______.
Onset of contraction and relaxation in smooth muscle is _______ and in skeletal muscle it is _______.
Force of contraction in smooth muscle is ______, and in skeletal muscle it is _______.
What is the cause of Urinary Bladder Hypertrophy?
enlargement of the prostate gland
What causes atherosclerosis?
lesions in endothelium of blood vessels
Cardiac muscle cells are similar to skeletal muscle in that they are _______.
Striations in cardiac muscle are ________ and connected by _________ at structures called _________.
branched, gap junctions, intercalated discs
The gap junctions between cardiac cells in the atria cause them to behave in some ways like a giant cell, a functional _______.
What permits both atria to contract simultaneously?
The T-tubules in cardiac muscle cells are located at the level of _______.
Where does Ca2+ for excitation-contraction coupling come from in cardiac muscle?
ISF, cisternae of SR
What channels open from the ISF during cardiac muscle excitation-contraction?
slow voltage-gated Ca2+/Na+
What channels are responsible for the plateau phase in excitation-contraction coupling in cardiac muscle?
voltage-sensitive Ca2+ channels
Does cellular depolarization in cardiac muscle produce contraction?
no (not unless trigger calcium enters the cells)
What causes repolarization in cardiac muscle cells?
outward diffusion of K+ through voltage-gated K+ channels
What causes relaxation of heart muscle?
Ca2+ actively transported from sarcoplasm into SR and interstitial fluid
Electrical synapses permit very fast current flow from what excitable cell to another through _________.
Gap junctions allow simultaneous contraction in _______ and _______ muscles.
The synaptic cleft is the gap between a ____________ and a __________.
presynaptic axonal membrane, postsynaptic dendrite membrane
Does action potential in the postsynaptic cell have any direct action on the presynaptic cell? Why?
no, neurotransmitter receptors are only found in the post-synaptic membrane
What is the bulbous enlargement and the end of each branch of a motor nerve fiber?
What isolates the neuro-muscular junction and isolates it from the surrounding fluid?
In synaptic transmission, an action potential traveling down a motor nerve fiber to the presynaptic terminal causes _____ channels to open.
In synaptic transmission, Ca2+ flows down its __________ _______ into the presynaptic terminal from the ________.
presynaptic terminal, interstitial fluid
In synaptic transmission, the influx of calcium inside the presynaptic terminal what to happen?
release of ACh from synaptic vesicles into the synaptic cleft
ACh is released by what method into the synaptic cleft?
What type of receptors does ACh bind to on the motor end plate?
ACh binding to the motor end plate cases opening of what channels in the motor end plate of a muscle fiber?
Na+ and K+ voltage gated channels
Depolorization of motor end plate causes action potential in the adjacent muscle tissue and is called what?
end plate potential
What terminates end plate potential?
Do miniature end plate potentials cause muscular contraction?
What are the two vesicle membrane proteins that act like "keys" that dock with protein "locks" at the synaptic knob membrane of the axon?
What is the axon membrane protein (the "lock" for docking and fusion of membrane)?
What do the neurotoxins in tetanus do?
prevent release of neurotransmitter from inhibitory neurons
What do the neurotoxins from botulism do?
prevent release of neurotransmitter from motor neurons
What are the two components of postsynaptic neurons?
receptor binding site, channel site
The postsynaptric neuronal membrane contains what two types of channels?
ion, second messenger activator
A neurotransmitter that opens Na+ channels is known as an ________ neurotransmitter.
A neurotransmitter that opens Cl channels is known as a __________ neurotransmitter?
A neurotransmitter that opens Cl channels will also open what channel?
The process of memory is achieved by activated a ____________ system.
The second messenger system is a group of proteins known as _____ proteins.
What is the activator portion of G-proteins?
What is the portion of of G-protein that attaches the G-protein to the interior of the cell membrane next to the receptor protein?
beta and gamma
EPSP opens what channels?
IPSP opens what channels?
How long are EPSPs and IPSPs generated for?
How long does it take to re-establish RMP after postsynaptic potential?
In motor neurons, APs are initiated where? EPSP and IPSPs originate where?
axon hillock, dendrite and cell body
Do action potentials attenuate with distance? Do EPSPs and IPSPs attenuate with distance?
How long is synaptic delay?
What is caused by depletion of neurotransmitter stores from the presynaptic terminals?
Dendrites of motor neurons cover a large _______ of 500 to 1000 micrometers in all directions from the cell body. This is useful for summation.
Rate of firing depends on what?
how much excitatory state is above threshold
Acidosis ________ the activity of neurons.
Alkalosis ________ the excitability of neurons.
What are the four general classifications of neurotransmitters?
quaternary amines, simple amines, amino acids, neuropeptides, other neurotransmitters
What enzyme catalyzes the reactions to synthesize ACh?
What is the only neurotransmitter that is used at the myoneural junction?
Where is ACh a inhibitory transmitter?
parasympathetic endings of vagus nerve
.What classifiation of neurotransmitter are catecholamines?
Norepinephrine, epinepherine, and dopamine are all what classification of neurotransmitter?
Serotonin and histamine are what type of neurotransmitters?
GABA, glutamate, and aspartate are what classification of neurotransmitters?
Endorphines, enkephalins, oxytocin, substance P and vasopressins are what classification of neurotransmitters?
What transmitter is responsible for long term memory and behavior effects?
What are three ways of eliminating neurotransmitters from the synaptic cleft?
diffusion from synaptic cleft, degradations by enzymes, active re-uptake of neurotransmitters
All sensory receptors are ________, because they convert one form of energy to another.
The stimulus that normally excites the receptor is known as what?
Which are pain receptors?
What type of receptors detect stimuli that arise at some distance from the body?
What type of receptors sense changes on the body surface?
What type of receptors detect stimuli that arise in the viscera?
What type of receptors detect the position and movement of the body?
How do two types of receptors know which type of stimulus they are supposed to detect?
Is receptor potential an action potential?
Receptor potential moves receptor ______ to threshold.
If the event is some change in the external energy, what type of graded potential will there be?
If the event is a signal from another neuron, the graded potential is called what?
If the graded potential change is spontaneous, it's called what?
Graded potential causes _____ current flows.
The greater the potential change, the _______ the current flow.
Current is carried by which ions?
The amplitude of current flow ________ with distance. The term for this potential is?
decreases, decremental potential
What type of receptors fire briefly when exposed to a constant stimulus and then become "silent"?
What type of receptors generate nerve impulses continually and thus adapt slowly?
Which of the following receptors adapt most quickly? Hair receptors, Muscle Spindle Receptors, Pacinian Corpuscles
Which is the fastest of the A fibers?
Which is the slowest of the A fibers?
What general Classification of Sensory nerve fibers are muscle spindle primary afferents, Golgi tendon organ afferent and alpha motor neurons?
What general Classification of Sensory nerve fibers are muscle spindle secondary afferent and specialized mechanoreceptors?
What is the general classification of sensory nerve fibers are afferent axons that transmit pain sensation?
What general classification of sensory nerve fibers are afferent axons that include crude touch and pressure receptors, tickle and chronic pain fibers?
Unmyelinated C fibers
Muscle spindle primary afferent fibers are classified as what in the alternate classification system?
In the alternate classification of sensory nerve fibers, what are golgi tendon organ afferent fibers?
In the alternate classification of sensory nerve fibers, what are muscle spindle secondary afferent fibers and cutaneous tactile receptors?
In the alternate classification of sensory nerve fibers, what are receptors for sharp picking pain, touch, and temp?
In the alternate classification of sensory nerve fibers, what are slow, chronic pain, crude touch, itch, and temperature information?
__________ fibers are regular contractile units of the muscle and contain actin and myosin filaments.
What are extrafusal skeletal muscle fibers innervated by?
What are intrafusal fibers innervated by?
What are the two types of intrafusal fibers?
nuclear bag fibers, nuclear chain fibers
What is the sensory innervation for the nuclear bag fibers and the nuclear chain fibers?
Ia afferent nerve
What are the sensory innervation fibers (Ia afferent nerve) also called?
primary afferent or annulospiral endings
What is the second sensory innervations, located near the ends of the nuclear chain fibers?
type II afferent nerves, secondary afferent, flower-spray
What is the motor innervation for muscle spindles?
dynamic and static gamma motoneurons
Dynamic Gamma motoneurons synapes on __________ fibers at motor end plates called ___________.
nuclear beg, plate endings
What are the two functional kinds of patterns of muscle spindles?
Which type of reflex is responsible for contraction of flexors as extensors relax to lift the hurt leg?
crossed extensor reflex
Which type of reflex is responsible for withdrawal from a painful stimulus?
Flexor withdrawal reflex
Which type of reflex causes the relaxation of the opposing muscles and the joint closes rapidly?