Neural mechanism involved in the release of urine is

Options

A. Reflex arc
B. RAAS
C. Micturition reflex
D. Parturition reflex

Answer

### Step-by-Step Solution:

1. **Understanding Micturition**:
- Micturition is the process of releasing urine from the urinary bladder. It is a complex process that involves both voluntary and involuntary actions.

**Hint**: Think of micturition as the act of urination, which involves both the bladder and the nervous system.

2. **Formation of Urine**:
- Urine is formed in the nephron, which is the functional unit of the kidney. Once formed, urine is transported to the urinary bladder for storage.

**Hint**: Remember that the nephron is crucial for urine production, and the bladder is where urine is stored.

3. **Storage of Urine**:
- The urine is stored in the urinary bladder until a signal is received from the central nervous system indicating that it is time to urinate.

**Hint**: The bladder acts like a reservoir for urine until it is full and signals the need to empty.

4. **Initiation of Micturition**:
- The process of micturition is initiated by the stretching of the urinary bladder walls as it fills with urine. This stretching activates sensory receptors.

**Hint**: Think of the bladder as a balloon that expands; when it gets too full, it sends a signal to the brain.

5. **Neural Mechanism**:
- The stretching of the bladder sends signals through sensory neurons to the spinal cord and then to the brain, which processes the information and sends back a signal to initiate the micturition reflex.

**Hint**: This is a reflex action, meaning it involves a quick response without needing conscious thought initially.

6. **Contraction and Relaxation**:
- The micturition reflex causes the smooth muscles of the bladder to contract and the urethral sphincter to relax, allowing urine to flow out of the bladder and through the urethra.

**Hint**: Visualize this as a coordinated action where the bladder squeezes while the exit (sphincter) opens.

7. **Completion of Micturition**:
- Once the bladder is emptied, the contraction stops, and the sphincter closes, completing the micturition process.

**Hint**: After urination, the bladder returns to its relaxed state, ready to fill again.

### Summary:
The neural mechanism involved in the release of urine is primarily the micturition reflex, which is triggered by the stretching of the urinary bladder, leading to a series of coordinated muscle contractions and relaxations that result in urination.