Spindle shape
Less mitochondria
Types of smooth muscle
Single-unit smooth muscle:
• Many gap junction electrical coupling
• Functional syncytium
• Visceral smooth muscle:
GI, Urinary tract, Uterus, Vessel
Multi-unit smooth muscle:
• Less gap junction separated contraction
• Fine control more than single type
• Large vessel, Bronchus, Iris m., Ciliary m., Arrector pili m