Quiz 2 Muscles Flashcards
Smooth muscle more often responds to which kind of signals?
local and hormonal
What kind of muscle is the diaphragm?
skeletal
What are 5 functions of muscle tissue
- Producing body movements
- Stabilizing body positions
- Regulating Organ Volume
- Flow of substances within the body
- Producing heat
What is extensibility
ability to stretch without damaging the tissue
What is the diameter of muscle fibers?
10-100 microns
What is the sarcolemma
plasma membrane of muscle cell + external lamina
What separates the muscles into fascicles
What seprates muscles fibers from one another
perimysium
endomysium
What kind of fibers make up endomysium/ maybe peri and epimysium as well?
reticular fibers/ type III collagen
light band is isotropic or anisotropic?
Isotropic
what does anisotropic mean?
block light
label, specifically M line
M line represents
attachment of adjacent myosin molecules
What are the 3 types of protein that comprise Myofibrils?
contractile, regulatory, and structural
Out of the three protein types that make up Myofibrils…what kind is Myosin Light Chain Kinase (MLCK)
regulatory
Which kind of muscles use MLCK and why?
smooth, no troponin complex in smooth
what is titin
what does it do
structural protein in myofibrils
starts at Z-line and binds to thick filament. acts as molecular spring
What is myomesin
what does it do
structural protein in myofibrils
.attaches myosin thick filaments at M line
What is nebulin
what does it do
structural protein in myofibrils
Regulates actin length
What is alpha actinin
what does it do
structural protein in myofibrils
anchors actin to Z disk
What is dystrophin
structural protein in myofibrils
What are the three classes of intermediate filaments in myofibrils and where are they
Where are they important
desmin,vinmentin, and syemin
They are inbetween the contractile proteins and
they are particularly importnat at the Z-disk
Troponin T binds to:
Troponin C binds to:
Troponin I binds to:
tropomyosin
calcium
actin and inhibits myosin binding
Each myosin filament has how many actin filaments surrounding it?
6
Myosin heads are N or C terminus?
N
