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Unformatted text preview: ism of melanocytes in healthy vs. response to UV radiation to produce malignancy.
What are the major criteria for determining malignancy in melanotic tumors?
3) Impulse arrives at axon terminus causing Ca++ to enter axon
Ca++ bind to ACh vesicles causing a release of Acetylcholine (ACh) into the synapse by exocytosis
ACh diffuses across the synapse to bind to receptors on the sarcolemma. This binding opens the chemically-gated ion channels causing Na+ to
enter the cell producing depolarization
4) When threshold depolarization occurs, an action potential is produced that will move along the sarcolemma
5) Local depolarization moves along reaching the voltage-gated channel
6) The voltage-gated Na+ channel opens, causing Na+ to enter the cell, excess Na+ entering causes a brief reversal of membrane potential
7) At this point the voltage-gated Na+ channel closes
8) Repolarization: Opening of K+ channels- K+ leaves the cell returning positive ions to the outside of the sarcolemma
9) ACh broken down by ACh-E
10) As the action potential/impulse travels along the sarcolemma and depolarizes/repolarizes, the impulse enters the cell through the T-tubules and
reach the sarcoplasmic reticulum, stimulating it
11) The SR releases Ca++ into the sacroplasm
12) The troponin changes shape moving the tropomyosin away from the active site on actin for binding of the myosin head
13) Immediately upon exposure of the active site the myosin head binds in an exothermic reaction
14) The myosin heads then swivel pulling the Z-lines closer together and shortening the sacrcomeres. Products of ATP hydrolysis, ADP and Pi are
15) ATP is taken up by the myosin heads as the cross bridges detach.
16) ATP is hydrolyzed and the energy transferred to the myosin heads as they cock and reset for next stimulus.
I. Tricepts Brachii is an antagonist to the biceps brachii, brachialis.
a. Action is the extension of the elbow. II. Internal intercostals is an antagonist to the External intercostals, pectoralis minor, diaphragm, scalenes, sternocleidomastoid
a. Action is the compression of the thorax. III. Extensor carpi radialis longus, extensor carpi radialis brevis is an antagonist to flexor carpi radialis, flexor carpi ulnaris, palmaris longus
a. Action is the extension and abduction of the wrist. IV. Infraspinatus, teres minor are antagonists to supraspinatus, deltoid
a. Action is the adduction and lateral rotation of the humerus. V. Serratus anterior is an antagonist to the rhomboid minor, rhomboid major
a. Action is the abduction of the scapula.
I. Temporalis and masseter
a. Closes the jaw II. Splenius capitus and trapezius
a. Extension of head and neck III. Rhomboid minor and rhomboid major
a. Adduction of scapula IV. Deltoid and supraspinatus
a. Abduction of arm V. Biceps brachii and brachialis
a. Flexion of the elbow Fixators I. Rhomboid major and rhomboid minor
Fixates scapula during the lifting of the arms
a. Fixates humerus
a. Fixates scapula
Semispinalis capitis, semispinalis cervicis, semispinalis thoracis, multifidis, rotators
a. Fixates torso during standing
1. Impulse arrives at axon terminus.
2. Calcium ion influx into axon.
3. Calcium binds to vesicles containing acetylcholine (Ach) and causes the vesicles to traverse to the axon terminal.
4. The vesi...
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- Fall '12