Term
| During skeletal muscle contraction which band stays the same length and which band shortens? |
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Definition
A band- maintains length
I band- shortens |
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Term
| In muscle cells what controls the internal ion concentration of calcium? |
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Definition
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Term
| Changes in the internal ion concentration of calcium has a profound effect on the actions of what? |
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Definition
| The contractile proteins of the muscles |
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Term
| Which contractile protein extends from the Z line to the bare portion of the myosin filament? |
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Definition
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Term
| What is the function of Titin? |
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Definition
| Prevents overextension of the sarcomeres and helps maintain the central location of the A bands. |
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Term
| Which contractile protein participates in the force from the contractile systemto the outside of cells via membrane-spanning proteins called integrins? |
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Definition
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Term
| What links integrins and the extracellular matrix? |
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Definition
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Term
| Explain the crossbridge cycle that drives muscle contraction. |
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Definition
| 1) ATP is bound to myosin at rest. 2) Ca activation leads to myosin-actin interaction. 3) ATP hydrolysis and product release. 4)Powerstroke. 5) Rotated and attached crossbridge is in a state of rigor. 6) Detachment occurs when a new ATP binds a myosin head. 7) ATP is again hydrolyzed. 8) process continues until ATP supply and continued Ca activation. |
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Term
| The switching action of the calcium-troponin-tropomyosin complex in skeletal and cardiac muscle is extended by the structure of the ________ filaments. |
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Definition
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Term
| In the calcium-troponin-tropomyosin complex, one troponin molecule via its tropomyosin connection can control what? |
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Definition
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Term
| Calcium control in striated muscle is controlled through thin filaments and is therefore termed what? |
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Definition
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Term
| Although the cellular control of smooth muscle contraction is also exercised by changes in calcium concentration, its effect is exerted on the thick filaments which is termed _________. |
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Definition
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Term
| Primary energy system for muscle contraction? |
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Definition
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Term
| At lower levels, fats can provide how much of the energy for contraction? |
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Definition
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Term
| When is protein used as an energy source for contraction? |
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Definition
| dieting, starvation, and heavy exercise |
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Term
| Type of contraction in which muscles stay the same length? |
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Definition
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Term
| Type of contraction in which muscles exert the same force? |
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Definition
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Term
| Type of contraction in which the force of contraction increases as the muscle shortens? |
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Definition
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Term
| Type of contraction in which the force of contraction decreases as the muscle shortens? |
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Definition
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Term
| Force of contraction in which the muscle is shortening? |
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Definition
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Term
| A muscle is extended by an external force or the muscle is lengthening in what type of contraction? |
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Definition
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Term
| contraction results in no movement due to partial activation opposing a load that is not maximal? |
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Definition
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Term
| What is the mechanism of action of curare as a post synaptic blockade? |
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Definition
| Binds to Ach receptors but does not open ion channels. The endplate potential is reduced in proportion to the number of receptors occupied by curare. |
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Term
| Mechanism of succincholyine as a post synaptic blockade? |
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Definition
| Binds to Ach receptors and causes the channels to open. prevents resetting of the inactivation gates of muscle membrane sodium channels near the endplate region and blocks subsequent action potentials |
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Term
| What are depolarizing blockers? |
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Definition
| Drugs that produce extremely long lasting endplate potentials |
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Term
| What is the mechanism of action of physostigmine? |
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Definition
| potent inhibitors of AChE and produce a depolarizing blockade. In carefully controlled doses, they can temporarily alleviate symptoms of myasthenia gravis |
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Term
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Definition
| the force a muscle experiences (exerts) after it has begun to shorten |
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Term
| What does a hemoglobin molecule consist of ? |
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Definition
| A globin portion and a four heme groups |
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Term
| What is the iron carrying portion of hemoglobin? |
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Definition
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Term
| What are the four main types of hemoglobin and what subunits do they consist of? |
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Definition
HbA- 2 alpha chains, 2 beta chains
HbA2- 2 alpha, 2 delta
Fetal hemoglobin- 2 alpha, 2 gamma
Embryonic- 2 alpha, 2 epsilon |
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Term
| What is the major inhibitory neuron of the CNS? |
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Definition
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Term
| Drugs that inhibit GABA cause what? |
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Definition
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Term
| The removal of GABA from the synaptic cleft is primarily by ? |
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Definition
| uptake into the presynaptic neuron and surrounding glial cells |
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Term
| What do inhibitors of Acetlycholinesterase cause? |
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Definition
| A depolarizing blockade which is caused from a long lasting end-plate potential that blocks subsequent action potentials due to the buildup of Ach in the terminal membrane. |
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Term
| What drug is an example of an AchE inhibitor? |
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Definition
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