Describe sympathetic neuropathway with neurotransmitters and receptors
short preganglion nerve, ACh with nicotinic receptors, long postganglion nerve, Norepinephrine with adrenergic receptors
Describe parasympathetic neuropathway with neurotransmitters and receptors
long preganglion nerve, ACh with nicotinic receptors, short postganglion nerve, ACh with muscarinic receptors
Name the exception to sympathetic pathway with receptor and neurotransmitter
Sweat glands used cholinergic receptors with ACh
Name the 4 classes of adrenergic receptors, what neurotransmitter it responds to, and location
Alpha 1 - NE>E, sympathetic
Alpha 2 - NE>E, Pancreas
Beta 1 - NE=E, heart, kidney
Beta 2 - E>NE, smooth musc.
Axon varicosities open what channel and use what neurotransmitter in response to an action potential
Calcium channel, NE
What is the role of Troponin and Tropomyosin?
Troponin is bound by Ca and moves Tropomyosin which exposes the myosin-binding site on the actin
What is the role of Titin and Nebulin
Titin provides stability and elasticity to myosin
Nebulin helps align actin
Describe the power stroke steps to muscle contraction.
Tight binding in the rigor state, ATP binds to myosin which causes myosin to release actin, ATP hydrolized (ADP + Pi) myosin head binds in cocked position, Release of Pi initiates the power stroke, ADP falls off and myosin resumes the rigor state.
Function of DHP receptors
responds to the action potential in the T-tubules, opens ryanodine receptors which let Ca out of the Sarcoplasmic reticulum
Intermediate muscle fibers
fast twitch oxidative, less fatigueable, both oxidative and glycolytic processes
fast twitch glycolytic, quick fatigue, anaerobic, large cell diameter (recruited last due to fatigue)
Group of muscle fibers controlled by a single somatic motor neuron. (small motor units for fine movements and large units for gross movements) (all fibers are of the same type)
Single unit smooth muscles
numerous gap junctions, unified contraction (found in blood vessels, intestinal tract)
Multi unit smooth muscle
No gap junctions, fine, graded contractions (found in iris, male reproductive tract)
Molecular events of smooth muscle contraction.
Ca channels open causing Ca release from SR, Ca binds to CaM, Ca-CaM activates MLCK, MLCK phosphorylates myosin heads (ATP), phosphorylated myosin heads increase muscle tension (no ATP needed to hold contraction)
Autonomic reflexes are monosynaptic or polysynaptic. Where are the synapses
Polysynaptic. at least one in CNS and another in an autonomic ganglion.
Golgi tendon organ function
detects strain in the tendon (sensory nerve endings interwoven among collagen fibers)
Lateral corticospinal tracts cross in the ____ while Anterior CST cross in the ______
Name right and left heart valves
Right AV (tricuspid), Left AV or Mitral (bicuspid), Pulmonary semilunar valve, aortic semilunar valve.
What allows waves of depolarization to pass through the cardiac muscles?
Desomosome and Gap junctions in the Intercalated disks transfer the electrical signal from cell to cell
Cardiac action potential steps
Na channels open and then close (-90 - 20mV), K close and Ca open (plateau 10mV), K open Ca close (repolarize -90)
Skeletal vs. Cardiac contraction length and refractory period
cardiac contraction is much longer (10X), cardiac refractory period lasts as long as the contraction (opposite of skeletal)
How do sympathetic and parasympathetic stimulation of the heart affect the action potential
sympathetic hypopolarizes the cell (due to high Ca levels) while parasympathetic hyperpolarizes the cell (due to extra K let out of the cell, muscarinic receptor activated K channels)
Baroreceptor function and location
stretch-sensitive mechanoreceptors used to monitor blood pressure.
Located in the walls of the carotid arteries and aorta.
sensory neurons to the CVCC, decrease sympathetic (dilation of arteries/veins), increase parasympathetic (decrease heart rate)
What organ converts Hb to bilirubin? where does bilirubin go?
Spleen, bilirubin is metabolized in the liver and excreted through bile
steps of platelet aggregation
collagen binds and activates platelets, release of platelet factors, attracts more platelets, forms platelet plug
common pathway steps
prothrombin converted to thrombin which converts fibrinogen to fibrin. (those fibers become part of the clot)
role of thrombin in clot resorption
thrombin creates plasmin from plasminogen. plasmin breaks down the fibrin.
name 4 lung volumes
residual volume, expiratory reserve volume, tidal volume, inspiratory reserve volume
Name the 4 lung capacities
Total lung capacity, inspiratory capacity (IRV + Vt), vital capacity (Vt + IRV + ERV), Functional residual capacity (ERV + RV)
Function of alveolar type I and type II cells
type I is thin for gas transport, type II produces surfactant
protective ventilation reflexes
bronchostriction in response to noxious particles
coughing - stimulation of carina
sneezing - nasal cavity irritation