From the following choices, choose the THREE, that would result in prevention of muscle contraction (in other words, which three descriptive changes below would result in flaccid paralysis of a muscle).   exocytosis of acetylcholine is constant, even without action potential   injection of botulinum toxin   calcium cannot be pumped back into the terminal cisternae   acetylcholine receptor remains open to sodium   active sites on actin a permanently exposed   dramatically increase the activity of acetylcholinesterase

Determine whether the following description is common to skeletal muscle, cardiac muscle or both skeletal and cardiac muscle. increase in tension during contraction of the muscle organ involves recruitment of other cells is primarily under the control of the autonomic nervous system all cells depolarize and contract during every contraction of the muscle organ different neurotransmitters can increase or decrease the rate of contraction action potentials begin electrical depolarization by a voltage-gated Na+ channel 1. skeletal muscle 2. cardiac muscle increase in cytosolic 3. skeletal muscle and cardiac muscle calcium increases tension in muscle cells prolonged depolarization is due to Ca2+ influx across the plasma membrane contraction is not under the control of hormones relaxation occurs when cytosolic calcium is reduced to resting levels increase in tension during contraction of single cells is associated with a higher frequency of action potentials

How is the muscular contraction stopped (i.e.: how does a muscle relax after contraction)? 1. The brain stops sending the nerve impulse that commands the muscle to contract, interrupting communication at the neuromuscular junction 2. Acetylcholineesterase (AChE) is released into the synaptic cleft to destroy any remaining Acetylcholine 3. No mechanism is necessary. When the antagonist begins to contract, it forces relaxation and stretch of the agonist muscle. 4. Relaxation occurs as the myosin heads are "snapped" off of the thick filaments. This interrupts the crossbridge and allows for muscles to stretch 5. Relaxation only occurs if the brain sends a "stop" signal to the muscle

Neuromuscular Junction: -Activation of nicotinic ACh receptors in the motor end plate results in both Na+ influx into and K+ efflux from the muscle fiber - An action potential in a motor neuron always produces a graded depolarization in the motor endplate and an action potential in the sarcolemma. -Acetylcholine released from the motor presynaptic terminal binds to voltage-gated ACh receptors in the motor endplate. -all of the above -a and b are right

place in correct order 1. ACH binds to receptors on the postsynaptic membrane 2. AP travels along the sarcolemma and T tubules 3. Ca++ ion bind to troponin 4.  Ca++ ions diffuse into the sarcoplasm 5. voltage-gated Ca++ ion channels in the sarcoplasmic reticulum open

Interruption of spindle discharge from a muscle causes contraction of the muscle to become jerky and irregular due to :-a- increased activity of reverberating circuits causing fluctuation of the motor discharge to the muscleb- increased activity of inhibitory interneurons causing oscillating inhibition of the α-motor neurons of the musclec- irregular discharge of excitatory inputs to the α-motor neurons of the muscle d- post-tetanic potentiation of the α-motor neurons of the muscle

please help me draw this

What is the effect of acetylcholine on skeletal muscle cells? Osalivary secretion food digestion decreased contraction rate O force generation parasympathetic regulation ◄ Previous Lact checked at

When an action potential arrives at the neuromuscular junction, acetylcholine is released into the synaptic cleft and binds to receptors in the postsynaptic membrane. Which of the following represents the correct order of the next series of events?   A. An action potential travels down the T tubules, depolarization spreads through the T tubules, Ca2+ is released from the sarcoplasmic reticulum, and myosin binds to actin.   B. Ca2+ is released from the sarcoplasmic reticulum, an action potential travels down the T tubules, depolarization spreads through the T tubules, and myosin binds to actin.   C. An action potential travels down the T tubules, depolarization spreads through the T tubules, Ca2+ is taken up by the sarcoplasmic reticulum, and myosin binds to actin.   D. T tubules are depolarized, Ca2+ is released from the sarcoplasmic reticulum, an action potential is created in the muscle cell, and myosin bonds to actin.   E. An action potential travels…

Describe what is happening overall in the first sentence. Then describe, in detail, what is happening in each step below. Include details about what is happening at steps 5 - 7 in terms of calcium and the contraction mechanism (from a different figure). (a) -Axon terminal of somatic motor neuron Muscle fiber ACh- potential Action Na+ Action potential- -Motor end plate- lell Ca2+ released Myosin thick filament 6 + + + ++