The
Musculoskeletal
System:
Support
and
Movement
Chris
Marzi
Senior
Seminar
Dr.
Paul
Smith
Introduc>on
• Invertebrate
Support
Systems
– Hydrosta>c
Skeletons
– Exoskeletons
• The
Vertebrate
Endoskeleton
– Skeletal
Development
– The
Skeletal
System
and
Homeostasis
– Movement
• Anatomy
and
Physiology
of
Vertebrate
Muscle
– Skeletal
Muscle
– Cardiac
Muscle
– Smooth
Muscle
The
Musculoskeletal
System
• The
musculoskeletal
is
the
interac>on
of
muscles
and
tendons
and
ligaments
and
bones
and
joints
and
associated
>ssues
that
move
the
body
and
maintain
its
form
and
allow
the
body
to
func>on.
• Also
called
the
“locomoter”
system.
Invertebrate
Support
Systems
Hydrosta)c
Skeletons
Exoskeletons
Hydrosta>c
Skeletons
Descrip)on
Earthworm
• Early
invertebrates
relied
on
the
manipula>on
of
fluids
for
movement.
• Limits
in
structural
ability
• Usually
only
found
in
organisms
that
reside
in
aqua>c
or
loose
soil
environments.
Hydrosta>c
Skeletons
• Water
cavity
that
allows
movement
is
manipulated
by
muscles
within
the
organisms.
• Organisms
tend
to
be
fragile.
• Due
to
structure,
limited
mobility.
• Segmenta>on
allows
for
beRer
movement.
Exoskeletons
Descrip)on
Carpenter
Ant
• Found
primarily
in
insects.
• Protects
well
against
water
loss
to
the
environment.
• Muscle
arrangement
differs
from
the
structure
of
vertebrates.
• Excellent
at
terrestrial
adapta>ons.
The
Vertebrate
Endoskeleton
Descrip)on
Human
Skeleton
• Composed
of
a
network
of
bone
and
car>lage.
• Rigid
with
the
excep>on
of
joints
that
allow
mobility
in
the
skeletal
framework.
• 206
bones
in
the
human
body.
The
Vertebrate
Endoskeleton
Skeletal
Development
•
•
•
•
•
•
The
skeleton
arises
from
mesoderm.
Early
forma>on
of
somites.
Forma>on
of
the
notochord.
Development
of
the
spinal
column.
Mesodermal
cell
migra>on.
Limb
buds
produce
the
appendicular
skeleton.
Skeletal
Development
The
Skeletal
System
and
Homeostasis
• Serves
maintain
balance
in
three
ways.
First:
Behavioral
responses
to
environmental
change.
Second:
Red
blood
cells,
or
at
least
parts
that
make
up
red
blood
cells
are
produced
in
the
bone
marrow.
Third:
The
skeletal
system
stores
minerals
that
are
able
to
be
released
as
needed.
Movement
• The
axial
por>on
of
the
skeletal
system
is
used
to
provide
stability
to
vital
organs
while
the
appendicular
provides
the
actual
mo>on.
• Appendicular
system
is
connected
by
ligaments
at
the
joints.
• Tendons
connect
the
skeletal
system
to
the
muscular
system.
• Origin
and
Inser>on.
• Flexion
and
Extension.
Various
Muscles
of
the
Human
Body
Anatomy
and
Physiology
of
Vertebrate
Muscle
• The
ability
for
internal
movement
as
well
as
external
movement
is
vital
to
all
animals.
• Every
animal
has
a
certain
system
of
movement.
• Internal
system
for
Amoeba
is
through
use
of
pseudopodia.
Primi>ve
Locamo>on
Systems
Cilia
Flagella
Skeletal
Muscle
•
•
•
•
ARached
to
the
skeletal
system.
Are
able
to
be
moved
by
voluntary
control.
Striated
muscle.
This
group
usually
makes
up
the
largest
muscle
type
in
an
organism.
Organiza>on
of
Skeletal
Muscle
The
Muscle
Fiber
Basic
unit
for
skeletal
muscle.
Mul>ple
Nucleus.
The
stria>on
seen
is
caused
by
myrofibrils.
Single
segment
of
a
myrofibril
is
called
a
sacromere.
• Movement
is
mediated
by
ATP
•
•
•
•
The
Muscle
Fiber
• Sarcomere
is
surrounded
by
a
Z‐line.
• Ac>n
and
Myosin
interact
in
any
given
sarcomere.
This
causes
the
muscle
to
contract.
• Ca2+
Ions
released
during
contrac>on.
Sarcomere
Structure
Cardiac
Muscle
Striated,
mononucleate
cells.
Form
networks.
Cells
are
connected
by
an
intercalated
disk.
Resembles
a
nervous
system
type
connec>on.
Structured
to
allow
independent
bea>ng
of
external
nervous
s>mula>on.
• Ac>on
poten>al
much
higher
than
skeletal
muscle.
•
•
•
•
•
Cardiac
Muscle
Smooth
Muscle
• Mononucleate
and
much
smaller
than
skeletal
muscle
fibers.
• Commonly
exist
in
>ghtly
packed
areas.
• Posses
non‐nueral
coordina>on.
• More
Ac>n
and
less
Myosin.
• Capable
of
maintaining
long
periods
of
contrac>on.
Smooth
Muscle
Sources
• Fried,
George
and
Hademenos,
George.
Schaum’s
Outline
to
Biology.
New
York:
McGraw‐Hill,
2009
• www.google.com/images