Innervation of heart in a living animals is primarily meant for :

Options

A. Initiation of heart beat
B. Regulation of heart beat
C. Release of acetylcholine only
D. Release of adrenalineonly

Answer

**Step-by-Step Solution:**

1. **Understanding Innervation**: Innervation refers to the supply of nerves to a specific body part. In this case, we are discussing the innervation of the heart.

2. **Role of the Nervous System**: The heart is primarily regulated by the autonomic nervous system, which controls involuntary bodily functions. The autonomic nervous system is divided into two main parts: the sympathetic nervous system and the parasympathetic nervous system.

3. **Sympathetic Nervous System**: The sympathetic nervous system is responsible for the "fight or flight" response. When activated, it increases heart rate and the force of heart contractions. This is crucial during times of stress or physical activity.

4. **Parasympathetic Nervous System**: In contrast, the parasympathetic nervous system promotes the "rest and digest" response. It decreases heart rate and conserves energy, allowing the body to relax and recover.

5. **Overall Function**: The primary function of the innervation of the heart by both the sympathetic and parasympathetic nervous systems is to regulate heart rate. This regulation allows the heart to respond appropriately to different physiological demands, ensuring that the body maintains homeostasis.

6. **Conclusion**: Therefore, the innervation of the heart in living animals is primarily meant for the regulation of heart rate.

**Final Answer**: The innervation of the heart in living animals is primarily meant for the regulation of heart rate.

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