Read the following statements.
Statement A: Post-ganglionic nerve fibres of sympathetic nervous system are adrenergic.
Statement B: Acetylcholine decreases the heart rate but adrenaline increases it. Choose the correct option

Options

A. Both statements are correct
B. Only statement A is incorrect
C. Only statement B is incorrect
D. Both statements are incorrect

Answer

To solve the question, we need to analyze both statements provided.

**Step 1: Analyze Statement A**
- Statement A states: "Post-ganglionic nerve fibres of the sympathetic nervous system are adrenergic."
- In the sympathetic nervous system, post-ganglionic fibers primarily release norepinephrine (noradrenaline) as a neurotransmitter. These fibers are indeed classified as adrenergic because they respond to adrenaline (epinephrine) and norepinephrine.
- Therefore, Statement A is **correct**.

**Step 2: Analyze Statement B**
- Statement B states: "Acetylcholine decreases the heart rate but adrenaline increases it."
- Acetylcholine is a neurotransmitter that, when released by the parasympathetic nervous system, acts on the heart to decrease the heart rate. This is a well-established physiological response.
- Adrenaline (epinephrine), on the other hand, is released by the adrenal glands and acts on the heart to increase the heart rate, particularly during stress or fight-or-flight situations.
- Therefore, Statement B is also **correct**.

**Step 3: Conclusion**
- Since both statements A and B are correct, the correct option is that **both statements are correct**.

**Final Answer: Both statements are correct.**

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