Transcript Skeletal, Muscular & Integumentary Systems

Skeletal & Muscular Systems
Copy everything in RED and
draw/label when told to
Skeletal system
• The skeletal system provides support, protects
internal organs, provides for movement, store
mineral reserves, and provides a site for blood
cell formation
• Composed of types of connective tissue called
bones, cartilage, and ligaments
The Skeleton
• There are 206 bones in a human adult skeleton
– Axial skeleton – supports central body and
consists of skull, vertebral column, and rib cage
– Appendicular skeleton – consists of bones of
arm, legs, pelvis and shoulders
• A newborn baby’s skeleton is mostly composed of cartilage,
which is replaced by bone during ossification.
• In adults, cartilage remains in places that need flexibility,
such as the tip of nose, the ears, and where the ribs meet
the sternum to allow for movement during breathing
Structure of Bones
• Mostly made of calcium and phosphorus, but
remember: bones are living things!
• Solid network of living cells and protein fibers
• Surrounded by a tough layer of connective tissue =
periosteum
• Dense compact bone layer contains a network of tubes
= Haversian canals, which have blood vessels and
nerves in them
• Less dense spongy bone layer adds strength to bones
without adding mass
• Two types of soft bone marrow within central cavity:
– Yellow = made up primarily of fat cells
– Red = produces RBCs, some WBCs, and fragments (platelets)
Figure 36-3 The Structure of Bone
Section 36-1
Spongy bone
Compact bone
Haversian
canal
Periosteum
Compact
bone
Bone
marrow
Spongy bone
Osteocyte
Artery
Periosteum
Vein
Joints
• Joints are places where one bone meets another bone
– Immovable joints = “fixed” allow no movement (for
example: skull)
– Freely movable joints = permit movement in one or
more directions
• Ball-and-socket: circular movement (shoulder/hip)
• Hinge: back and forth motion (elbow/knee)
• Pivot: one bone rotates around another (radius and
ulna in arm)
• Saddle: one bone slides in two directions (carpals and
metacarpals in wrist)
• Ligaments connect bones to other bones.
Figure 36-4 Freely Movable Joints
and Their Movements
Section 36-1
Ball-and-Socket Joint
Pivot Joint
Clavicle
Humerus
Ball-andsocket
joint
Radius
Hinge Joint
Scapula
Pivot
joint
Saddle Joint
Ulna
Humerus
Femur
Patella
Fibula
Metacarpals
Tibia
Hinge
joint
Saddle joint
Carpals
COPY ALL TERMS ON THIS SLIDE
CLAVICLE/ collar bone
SCAPULA / shoulder blade
CRANIUM/ skull
MANDIBLE/ lower jaw
HUMERUS/ upper arm bone
STERNUM/ breastbone
RIBS/ ribs
VERTEBRAE/ back bone
RADIUS/ top lower arm bone
PELVIS / hip bone
ULNA/ bottom lower arm bone
CARPALS/ wrist bones
FEMUR / thigh bone
PHALANGES/ fingers
PATELLA/ kneecap
TIBIA/ shin bone
FIBULA / lower leg bone
TARSALS/ ankle bones
PHALANGES/ toes
Muscular system
• The muscular system provides the forces that
put the body in motion
Types of Muscle Tissue
• There are 3 different types of muscle tissue:
– Skeletal: usually attached to bone, responsible for
voluntary movements (typing, dancing, winking), appears
to have alternating dark and light bands = striated muscle,
controlled by CNS
– Smooth: not under voluntary control, not striated,
do not need nerve stimulation because they are
connected by gap junctions that allow electrical impulses to
travel from one cell to the next (digestive tract, blood
vessels, pupils)
– Cardiac: only found in the heart, striated, not under
voluntary control
Muscle Contractions
• Occurs when thin muscle filaments slide over
thick muscle filaments
– Thick have myosin protein
– Thin have actin protein
• The energy for muscle contractions is supplied
by ATP
Interactions of Muscles and Bones
• Skeletal muscles move bones by contracting,
or pulling (muscles can ONLY pull)
• Tendons connect muscles to bones
• Skeletal muscles work in pairs: one contracts
and the other relaxes
MASSETER
BICEPS
STERNOCLEIDOMASTOID
TRICEPS
DELTOID
PECTORALIS MAJOR
RECTUS ABDOMINIS
SARTORIUS
GASTROCNEMIUS
RECTUS FEMORIS
TIBIALIS ANTERIOR
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MUSCLE FUNCTIONS
Masseter– moves the mandible
Sternocleidomastoid- flex & rotate the head
Biceps- flex the elbow
Triceps- extend the elbow
Deltoid- raise the arm
Pectoralis Major- pulls arms toward center of body
Rectus abdominis- bends body forward
Sartorius- rotates the thigh
Gastrocnemius- pulls toes down
Rectus femoris- extends lower leg
Tibialis Anterior- pulls toes up