Transcript Skeletal System

Skeletal System
Bone formation: bones
start as cartilage and slowly
it is replaced by bone
Structures:
bone
tendons
ligaments
cartilage
Functions:
1. Gives Shape and support to the body
2. Protect your internal organs
3. Major muscles attach to bones to help
you move
4. Blood cells are formed in the bone. (The
tissue called marrow)
5. Store calcium and phosphorous
compounds (calcium and phosphorous
compounds make bones hard)
Bone
• Major organs of the
skeletal system
• Adult skeleton composed
of 206 bones
• Store minerals
• In certain bones, bone
marrow produces blood
cells
Structure of Bones
Periosteum :
thin tough layer that
covers all the bones,
except the part of the
bone that is in the
joint. Blood vessels
in the pariosteum
carry the nutrients to
the bone and cell
that repair and cause
growth are here.
Compact bone:
right under the
periostreum this layer
is the hard strong
part. This layer gives
bones strength
contains deposits of
calcium phosphate.
Spongy Bone:
is locate at the end
of the long bones
like those in your
arms and legs. This
part of the bone has
lots of open spaces
which keeps the
bones light weight.
Cavities:
are the center of the long
bones and contain the
marrow
Marrow:
some marrow is red some
yellow. Red marrow
produced red blood (2 to
3 million per second)
cells, yellow marrow is
made up of fat.
Connective Tissue
Ligament
• Connects bone to bone
Tendon
• Connects skeletal muscle
to bone
Skeletal
muscle
Tendon
Bone
Cartilage: soft and flexible tissue that
provides padding in between bones.
Ligament
Connect Bone to Bone
Tendon
Connect Muscle to Bone
Joints Of the Human Body
Any place
where two or
more bones
come
together .
Some joints
move and
others do not.
Types of Joints
• Immovable
– Skull
– Pelvis
• Moveable
–
–
–
–
Pivot
Ball & socket
Hinge
Gliding
Immovable Joint
No movement
takes place at
these type of
joints
Ball and Socket Joint
Bone with a
rounded end
that fits into
a cuplike
cavity on
another
bone
Gliding Joint
One part of a
bone slides
over another
bone
Pivot Joint
One bone
rotates in a
ring of another
bone that
does not
move.
Hinge Joint
Back-and-forth
movement like
hinges on a door
Muscular System
600 Muscles
Types of Muscle Movement
Involuntary- Automatically move without
you knowing.
Voluntary- You control the movements.
Types of Muscles
Smooth Muscles- Which include the
muscles of internal organs and blood
vessels. These muscles move
involuntary.
Cardiac Muscle- Found only in the heart
and also involuntary.
Skeletal Muscles- Are voluntary and help
you move.
Smooth Muscle
Digestive organs
Makes up 7-8% of your
muscles
Involuntary
Cardiac Muscles
Only found in the heart.
Involuntary.
Makes up 3% of your muscles.
By age 70 heart contracts 2.5 billion
times (assume resting heart beat).
Skeletal Muscles
Makes up 90% of your muscles.
Voluntary- These are the muscles that you
can move.
Types of Injuries
Strain- Muscle “pull” or “strain” Tearing a muscle fiber(s),
followed by bleeding or swelling
of muscle
Muscle Cramp - Prolonged
contraction of muscle
Muscles and Movement
Muscles can only contract & relax.
Muscle fibers line up and pull the tendon attached to
the bone to cause movement.
Muscle Pairs
Muscle fibers line up and
pull the tendon attached
to the bone to cause
movement.
Your muscles work in
teams to move your
body. As one group of
muscles is contracting
another group is relaxing
An example of this is
your Bicep and Tricep.
http://www.sirinet.net/~jgjohnso/muscle.html
Summary
• Explain how the Nervous System, Skeletal
System and Muscular System all work
together to create movement.
Systems Working Together
1. Our brain sends a message (NS)
2. The message travels down your spinal
cord (NS)
3. The motor neuron fires a message (MS)
4. The muscle contracts (MS)
5. The muscle shortens pulling on the
tendon (MS and SS)
6. The bone connected to the tendon
moves (SS)