Urination will be caused by simultaneous:

1. contraction of smooth muscle of bladder and relaxation of urethral sphincter
2. relaxation of smooth muscle of bladder and contraction of urethral sphincter
3. contraction of smooth muscle of bladder and urethral sphincter
4. relaxation of smooth muscle of bladder and urethral sphincter
Subtopic:  Micturition Reflex |
 87%
Level 1: 80%+
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