Muscles Flashcards
(9 cards)
Why is smooth muscle not striated?
It lacks the sarcomere
How are unitary smooth muscles connected?
Connected by gap junctions
What are vercosities?
They are neurotransmitters that release different chemicals to stimulate the smooth muscle cells
How do gap junctions work?
They allow the flow of charge to each muscle cell to stimulate them - they are electrically coupled
How is a multiunit smooth muscle cell activated?
Each cell has its own nerve stimulator - not connected by gap junctions
What controls the smooth muscle cells?
Smooth muscle cells are controlled by the autonomic nervous system
Where are the calcium gated ion channels located in smooth muscle?
Located in the caveolae and they open when the membrane potential reaches the threshold
Does smooth muscle have troponin?
No, it has calmodulin instead
How is MLCK activated and what does it do?
Activated by the calcium/calmodulin complex and adds a phosphate onto the myosin.
This stimulates the myosin ATPase activity
