Front | Back |
What are the characteristics of smooth m
|
No striations
Involuntary Visceral |
What are the characteristics of cardiac m
|
Striated
Involuntary Cardiac |
What is the location of smooth m
|
Hollow organs
|
What are ex of hollow organs
|
Vessels
Gastrointestinal organs (GI) Respiratory passages Glands Inside the eye (pupil and lens) Arrector pili to hair follicles |
Each of the hollow organs are different in what
|
Fiber arrangement
Innervation Response to stimuli |
What are 2 general types of smooth m
|
Single unit
Multiunit |
What is single unit
|
All united into one functioning group, most
|
What is multiunit
|
More like skeletal
Independent cells Individually innervated (ANS) Recruitment for strength, eye, large airways & arteries, arrector pili |
What is the characteristics of single unit
|
Thick & thin filaments less regularly arranged, longer, spiral through cell
Ca2+ still signal for contraction Cells connected by gap junctions Pacemaker |
What is the characteristics of multiunit
|
Thick & thin filaments less regularly arranged, longer, spiral through cell
Ca2+ still signal for contraction |
What is different about the Ca2+ signal for contraction in single unit and multiunit
|
Less SR and no troponin so Ca2+ works differently, some from extracellular
|
How does Ca2+ work differently in single unit and multiunit
|
Activates calmodulin and kinase
Phosphorelates myosin heads and sliding occurs Contraction ends when Ca2+ drops and P removed Contraction much slower but can last much longer Much less energy used than skeletal |
What type of synapse is in gap junctions
|
Electrical synapse
|
What is pacemakers
|
Some can self-depolarize
|
How many layers are in single-unit of smooth mm and how is it organized
|
2 layers of m with opposite fiber directions
Peristalsis |