Smooth Muscle Flashcards
1
Q
what is the function of smooth muscle
A
continuous contractions of relatively low force. i.e in resp sys, digestive sys, urinary sys
2
Q
is smooth msucle striated
A
no
3
Q
is smooth muscle voluntary or involuntary
A
involuntary
4
Q
describe how smooth muscle contracts.
A
no striations or sarcomeres. actin + myosin are still present, but are arranged into focal densities. these dense bodies are attached to the sarcolemma similar to Z disks in skeletal muscle.
Calcium-calmodulin complex activates myosin kinase, which activates the mysosin heads by phosphorylation. the heads attach to actin binding sites and pull on thin filaments
5
Q
what regulates cross bridge formation in smooth msucle
A
calmodulin protein
6
Q
A
