Zusammenfassung der Ressource
Muscle
- Organization
- approx 600 skeletal muscles
- approx half our body weight
- 3 kinds of muscle tissue; skeletal, cardiac, smooth
Anmerkungen:
- 3 kinds of tissue:
skeletal, cardiac, smooth
- Specialized for one major
purpose: converting chemical
energy in ATP into mechanical
energy of motion
- Myology= the study of the muscular system
- Function of Muscle
- Movement
- Move from place to
place, movement of
body parts, contents,
breathing, circulation,
feeding and digestion,
defecation, childbirht
- Stability:
- Maintain posture,
prevents unwanted
movements.
Antigravity
muscles-resist pull of
gravity stabilize
joints
- Control of
openings and
passageway
- Sphincters:
internal muscular
rings control
movement of
food, bile, blood,
and other
material
- Heat Production
- as much as 85% of body heat
- Connective Tissue of
Muscle
- Endomysium
- Perimysium
- Epimysium
- Fascia
- sheet of connective
tissue that separates
neighboring muscles or
groups from each other
and subcutaneous
tissue.
- Fibrous
sheath
surrounding
the entire
muscle.
- outer
surface
grades into
the fascia.
- Inner surface sends
projections between
fascicles to form
perimysium.
- Slightly
thicker
layer of
connective
tissue.
- Fascicles:
bundles of
muscle fibers
wrapped in
perimysium.
- Carry larger
nerves and blood
vessesls, and
stretch receptors.
- thin sleeve of
loose connective
tissue.
Surroundes each
muscle fiber
- Allows room
for capillaries
and nerve
fibers to reach
each muscle
fiber.
- Shapes and classification
according to fascicle
orientation
- Fusiform
- Parallel
- Triangular (convergent)
- Pennate
- Circular (sphincters)
- ring around
body
opening
- orbicularis oculi,
urethral, anal
sphincters.
- fascicles
insert
obliquely
on a
tendon
- unipennate,
bipennate or
multipennate
- palmar
interosseus, rectus
femoris and deltoid
- feather
shaped
- fan-shaped, broad
at origin, tapering to
a narrower
insertion.
- pectoralis
major,
temporalis
- Has uniform
width and
parallel
fascicles.
- can span
longer
distances
than other
shapes.
- rectus
abdominis,
zygomaticus
major
- thick in
middle,
tapered at
ends
- biceps brachii,
gastrocnemius
- Muscle
Attachments
- Indirect attachment to
bone
- Tendons
- tendons bridge the
gap between muscle
ends and bony
attachment.
- Collagen fibers
of endo-, peri-,
and epimysium
continue into the
tendon
- Very strong
structural
continuity from
muscle to bone
- biceps
brachii,
Achilles
tendon
- Direct (fleshy) attachment
to bone
- Epimysium continues as
tendon merges into
periosteum as perforating
fibers.
- muscle seems to
immerge directly
from bone
- margins of
brachialis, lateral
head of triceps
brachii
- Attachment
to dermis
- some skeletal
muscles do not insert
on bone, but in
dermis of skin
- muscles of
facial
expressions
- Muscle Origins and
Insertions
- Origin
- Belly
- Insertion
- Mobile
- bony
attachment to
mobile end of
muscle
- Middle
- thicker, middle
region of
muscle
between origin
and insertion
- bony
attachment
at stationary
end of
muscle
- Stable