HBIO 320 EXAM 1 QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS GRADED A++ LATEST UPDATE
fusiform muscle fiber arrangement
longitudinal, fibers parallel with tendon
parallel interrupted fiber arrangement
rectus abdominis
convergent muscle fiber arrangement
some fibers don't make it to the tendon
pennate fiber arrangement
fibers insert into the tendon at oblique angles, fibers are shorter than muscle length
pennate fiber arrangement pros
increase in cross sectional area, since intrinsic muscle force is fixed, more CSA = more
force
pennate fiber arrangement cons
- force is reduced by cos(angle), the more oblique the muscle inserts, the less force is
transferred
- muscles shorten less because of the angle
Whole muscle
Belly
Muscle Fascicle
bundle of muscle fibers
,myofiber
Muscle cell, muscle fiber
Myofibril
sarcomeres in series, subcellular organelle
sarcomere
z disc to z disc, individual contractile unit, simplest contractile unit that can provide force
myofilament
actin(thin)/myosin(thick)
cytoskeletal structures and examples
z-line/disc
m-line
intermediate filaments (titn)
Proteins that add structure to skeletal muscle to maintain efficiency
epimesium
-surrounds belly of muscle
-comprised of collagen/elastin
-amorphous ground substance holds everything together
perimysium
-surrounds muscle fascicle
-comprised of collagen/elastin
-amorphous ground substance holds everything together
collagen
, primary constituent of epi, peri, and endomysium
collagen synthesis
-fibroblasts in ER create procollagen which gets excreted and acted on by procollagen
peptidase.
-self assembles into collagen with self aggregating ends
endomysium structure
-envelopes each muscle cell (myofiber) tendon to tendon
-comprised of collagen, elastin, EC matrix
endomysium function
- scaffolding for delveloping or regenerating muscle
- conduit for nerves and blood vessels
- connects with plasmalemma
- force transduction
sarcolemma
basement membrane and plasmalemma
basement membrane
right below endomysium, transmembrane structures that allow internal and external
muscles to connect
reticular lamina
associated with the reticular fibers of the endomysium
basement lamina
lamina densa and lucida
laminin structure
COMPLETE SOLUTIONS GRADED A++ LATEST UPDATE
fusiform muscle fiber arrangement
longitudinal, fibers parallel with tendon
parallel interrupted fiber arrangement
rectus abdominis
convergent muscle fiber arrangement
some fibers don't make it to the tendon
pennate fiber arrangement
fibers insert into the tendon at oblique angles, fibers are shorter than muscle length
pennate fiber arrangement pros
increase in cross sectional area, since intrinsic muscle force is fixed, more CSA = more
force
pennate fiber arrangement cons
- force is reduced by cos(angle), the more oblique the muscle inserts, the less force is
transferred
- muscles shorten less because of the angle
Whole muscle
Belly
Muscle Fascicle
bundle of muscle fibers
,myofiber
Muscle cell, muscle fiber
Myofibril
sarcomeres in series, subcellular organelle
sarcomere
z disc to z disc, individual contractile unit, simplest contractile unit that can provide force
myofilament
actin(thin)/myosin(thick)
cytoskeletal structures and examples
z-line/disc
m-line
intermediate filaments (titn)
Proteins that add structure to skeletal muscle to maintain efficiency
epimesium
-surrounds belly of muscle
-comprised of collagen/elastin
-amorphous ground substance holds everything together
perimysium
-surrounds muscle fascicle
-comprised of collagen/elastin
-amorphous ground substance holds everything together
collagen
, primary constituent of epi, peri, and endomysium
collagen synthesis
-fibroblasts in ER create procollagen which gets excreted and acted on by procollagen
peptidase.
-self assembles into collagen with self aggregating ends
endomysium structure
-envelopes each muscle cell (myofiber) tendon to tendon
-comprised of collagen, elastin, EC matrix
endomysium function
- scaffolding for delveloping or regenerating muscle
- conduit for nerves and blood vessels
- connects with plasmalemma
- force transduction
sarcolemma
basement membrane and plasmalemma
basement membrane
right below endomysium, transmembrane structures that allow internal and external
muscles to connect
reticular lamina
associated with the reticular fibers of the endomysium
basement lamina
lamina densa and lucida
laminin structure
