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Hello students, in this video i will be answering multiple questions regarding autonomic nervous system beginning with the first question.
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The schematic representation provided in question 1 is sympathetic division of autonomic nervous system.
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This sympathetic division is responsible for fight or flight response and it prepares the body for action.
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In the context of heart innervation, sympathetic fibers originate from the thoracic region of the spinal cord and extend to the heart.
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The neurotransmitter released in the synapse between two neurons in sympathetic innervation is acetylcholine.
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It is released from the presynaptic neuron into the synaptic cleft.
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The neurotransmitter released in the synapse with the heart in sympathetic innervation is norepinephrine.
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It binds to adrenergic receptors present on the target heart cells.
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The target heart cells have adrenergic receptors, specifically beta 1 adrenergic receptor.
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These receptors are responsible for receiving norepinephrine released by sympathetic neurons.
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The effect of sympathetic innervation on the heart is multifaceted.
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Activation of beta 1 adrenergic receptor leads to increased in heart rate, increased force of contraction, dilation of coronary arteries ultimately leading to promoting increased blood flow to the heart.
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These effects prepare the heart to increased activity during the times of stress or physical exertion.
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Next question, that is question number two.
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The schematic representation presented in question two is parasympathetic division of autonomic nervous system.
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This parasympathetic division is responsible for rest and digest response, promoting relaxation and conservation of energy.
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In terms of heart innervation, parasympathetic fibers originate from the brainstem and sacral region of the spinal cord and extend to the heart.
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Next question b.
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The neurotransmitter released in the synapse between two neurons in parasympathetic innervation is acetylcholine.
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It is released from the presynaptic neuron into the synaptic cleft.
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Next question c.
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The neurotransmitter released in the synapse with the heart in parasympathetic innervation is also acetylcholine.
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It binds to cholinogenic receptors present on the target heart cells.
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Next question d.
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The target heart cells have cholinergic receptors specifically m2 muscarinic receptors.
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These receptors receive acetylcholine released by parasympathetic neurons.
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Next question e.
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The effect of parasympathetic innervation on the heart is opposite to that of sympathetic innervation.
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Acetylcholine binding to muscarinic receptors leads to a decrease in heart rate, decreased force of contraction, constriction of coronary artery, ultimately reducing the blood flow to the heart.
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These effects help conserve energy and promote relaxation.
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Moving on to the third question.
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Here we need to match the effects with the increased activity of either sympathetic or parasympathetic nervous system.
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The first effect is increases liver storage of glucose...