Smooth Muscles

Question 1

Phosphorylates and activates myosin heads

Answer 1

Myosin Light Chain Kinase (MLCK)

Question 2

Dephosphorylates and deactivates myosin heads

Answer 2

Myosin Light Chain Phosphatase (MLCP)

Question 3

Binds with calcium

Answer 3

Calmodulin

Question 4

Inhibits muscle contraction

Answer 4

Caldesmon and Calponin

Question 5

Analogous to Z lines

Answer 5

Dense bodies

Question 6

Rudimentary T Tubules

Answer 6

Caveoli

Question 7

One nerve, multiple muscle fibers that may act on their own

Controlled mainly by nerve signals (Ach, NE)

(-) gap junctions

NO TRUE AP (no propagation)
Junctional potential only

(-) spontaneous reactions

Answer 7

MULTI UNIT SMOOTH MUSCLE

i.e. ciliary eye muscle, iris, piloerector muscle, vas deferens

Question 8

One nerve, multiple muscle fibers that ACT TOGETHER AS ONE

Controlled mainly by nerve signals (Ach, NE) and non nerve signals (hormone, stretch, local factors)

(+) gap junctions

Slow waves, spike potentials and plateau potentials

may exhibit spontaneous reactions

Answer 8

SINGLE UNIT SMOOTH MUSCLE/UNITARY SMOOTH MUSCLE/SYNCYTIAL SMOOTH MUSCLE/VISCERAL SMOOTH MUSCLE

i.e. intestines, bile ducts, uterus, ureter

Question 9

Responsible for relaxation of contracted smooth muscles and formation of latch bridges

Answer 9

Dephosphorylation of actomyosin