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Assertion : Neural signals through sympa...

Assertion : Neural signals through sympathetic nerves can increase the strength of ventricular contraction
Reason : Parasympathetic neural signals synergistically act with sympathetic neutral signal to increase the cardiac output.

A

If both assertion and reason are true and reason is the correct explanation of assertion

B

If both assertion and reason are true but reason is not the correct explanation of assertion

C

If assertion is true but reason is false

D

If both assertion and reason are false

Text Solution

AI Generated Solution

The correct Answer is:
To solve the given assertion-reason question, we will analyze both the assertion and the reason step by step. ### Step 1: Analyze the Assertion **Assertion**: Neural signals through sympathetic nerves can increase the strength of ventricular contraction. - The sympathetic nervous system is responsible for the "fight or flight" response, which includes increasing heart rate and the strength of heart contractions. - This is primarily due to the release of neurotransmitters like norepinephrine (noradrenaline), which enhance the contractility of the heart muscle (ventricles). - Therefore, the assertion is **true**. ### Step 2: Analyze the Reason **Reason**: Parasympathetic neural signals synergistically act with sympathetic neural signals to increase cardiac output. - The parasympathetic nervous system is responsible for the "rest and digest" functions, which generally oppose the sympathetic nervous system. - It primarily uses acetylcholine as a neurotransmitter, which decreases heart rate and has an inhibitory effect on cardiac activity. - Thus, the parasympathetic signals do not act synergistically with sympathetic signals; rather, they act antagonistically. - Therefore, the reason is **false**. ### Step 3: Conclusion Based on the analysis: - The assertion is true, and the reason is false. - Thus, the correct option is **C**: Assertion is true but reason is false. ### Final Answer The correct answer is **Option C**: Assertion is true but reason is false. ---
To solve the given assertion-reason question, we will analyze both the assertion and the reason step by step. ### Step 1: Analyze the Assertion **Assertion**: Neural signals through sympathetic nerves can increase the strength of ventricular contraction. - The sympathetic nervous system is responsible for the "fight or flight" response, which includes increasing heart rate and the strength of heart contractions. - This is primarily due to the release of neurotransmitters like norepinephrine (noradrenaline), which enhance the contractility of the heart muscle (ventricles). - Therefore, the assertion is **true**. ...
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