PHYSIOLOGY
SYNAPTIC PHYSIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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1.Acetylcholine diffuses across the gap at the neuromuscular junction2.The distal end of a motor neuron releases acetylcholine. 3.The muscle fiber membrane is stimulated, and a muscle impulse travels deep into the fiber through the transverse tubules and reaches the sarcoplasmic reticulum. 4. Calcium ions diffuse from the sarcoplasmic reticulum into the sarcoplasm and bind to troponin molecules. 5. Troponin and tropomyosin interact to expose binding sites on actin6. Actin and myosin filaments form linkages7. Myosin cross bridges pull actin filaments inward.8. The muscle fiber shortens as a contraction occurs.
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1.The distal end of a motor neuron releases acetylcholine. 2. Acetylcholine diffuses across the gap at the neuromuscular junction3.The muscle fiber membrane is stimulated, and a muscle impulse travels deep into the fiber through the transverse tubules and reaches the sarcoplasmic reticulum. 4. Calcium ions diffuse from the sarcoplasmic reticulum into the sarcoplasm and bind to troponin molecules. 5. Troponin and tropomyosin interact to expose binding sites on actin6. Actin and myosin filaments form linkages7. Myosin cross bridges pull actin filaments inward.8. The muscle fiber shortens as a contraction occurs.
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1.The muscle fiber membrane is stimulated, and a muscle impulse travels deep into the fiber through the transverse tubules and reaches the sarcoplasmic reticulum.2.The distal end of a motor neuron releases acetylcholine. 3. Acetylcholine diffuses across the gap at the neuromuscular junction4. Calcium ions diffuse from the sarcoplasmic reticulum into the sarcoplasm and bind to troponin molecules. 5. Troponin and tropomyosin interact to expose binding sites on actin6. Actin and myosin filaments form linkages7. Myosin cross bridges pull actin filaments inward.8. The muscle fiber shortens as a contraction occurs.
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1.Actin and myosin filaments form linkages2.Myosin cross bridges pull actin filaments inward.3.The distal end of a motor neuron releases acetylcholine. 4. Acetylcholine diffuses across the gap at the neuromuscular junction5.The muscle fiber membrane is stimulated, and a muscle impulse travels deep into the fiber through the transverse tubules and reaches the sarcoplasmic reticulum. 6. Calcium ions diffuse from the sarcoplasmic reticulum into the sarcoplasm and bind to troponin molecules. 7. Troponin and tropomyosin interact to expose binding sites on actin8. The muscle fiber shortens as a contraction occurs.
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Detailed explanation-1: -Skeletal Muscle Contraction. (a) The active site on actin is exposed as calcium binds to troponin. (b) The myosin head is attracted to actin, and myosin binds actin at its actin-binding site, forming the cross-bridge. (c) During the power stroke, the phosphate generated in the previous contraction cycle is released.
Detailed explanation-2: -Depolarisation and calcium ion release. Actin and myosin cross-bridge formation. Sliding mechanism of actin and myosin filaments. Sarcomere shortening (muscle contraction)
Detailed explanation-3: -1) An AP travels down the axon. to the axon terminal. 2) Electrical gated calcium channels open. 3) Calcium causes the vesicles to. 4) ACH diffuses across the synaptic cleft. 5) ACH binding opens ion channels. 6) If the muscle reaches the threshold (-55mv) at the motor end plate. 7) ACH is broken down by.
Detailed explanation-4: -Step 1: Calcium ions. Calcium ions are released by the sarcoplasmic reticulum in the actin filament. Step 2: cross bridge forms. Step 3: Myosin head slides. Step 4: skeletal muscle contraction has occurred. Step 5: Cross bridge breaks. Step 6: troponin.