Skeletal system Flashcards
Tendons
Connect muscle to bone
Ligaments
Connect bone to bone
Cartilage
cushion between bones
Long Bones
longer than they are wide (ex: femur, humerus, Metacarpals, Metatarsals
Short bones
- as wide as they are long (ex: carpals, tarsals)
- provides support and stability with little movement
Flat bones
- Sound, strong and flat (ex: scapula, sternum, cranium)
- provides protection to the bodies vital organs and being a base for muscular attachment
Irregular bones
Nonsymmetrical shape
EX: Skull, Vertebra
Sesamoid Bones
round bones found near joints (e.g., the patella)
Superior
toward the head
Inferior
away from the head
Anterior
toward the front
Posterior
toward the back
Medial
toward the midline
Lateral
towards the side
Clavicle
gives greater mobility to the shoulder joint when movement is taking place
Scapula
allows the arm to attach to the trunk portion of the skeleton
Bones of the upper limb
humerus, radius, ulna, carpals, metacarpals, phalanges
Bones of the lower limb
patella, tibia, fibula, pelvis
axial skeleton
forms the long axis of the body and includes the bones of the skull, vertebral column, and rib cage
vertebral column
24 moveable vertebrae in 3 sections:
1. Cervical: 7 vertebrae- C1-C7
2. Thoracic: 12 vertebrae- T1-T12
3. Lumbar: 5 vertebrae- L1-L5
appendicular skeleton
bones of the shoulder, pelvis, and upper and lower extremities
fibrous (immovable) joints
No movement (skull)
Cartilaginous (slight movable) Joint
only slight movement (spinal column)
synovial (moveable) joints
- freely movable joints
- Cartilage covers bones near synovial joints so that ligament attachment can occur (hyaline)
- Between two bones in these joints, there is a membranous sac called bursa
- Bursae produces synovial fluid which covers the ends of the bones allowing smooth movement
Planar joint (gliding)
- Range of motion is limited and does not involve rotation
- Found in carpal bones and tarsal bones, and between the vertebrae
hinge joint
Joint between bones (as at the elbow or knee) that permits motion in only one plane
Pivot joint
- Allows for rotation around the length of a bone, and only allows for rotation. (example: wrists)
condyloid joint
allows angular movement along two axes (example:wrist and fingers)
saddle joint
allow angular movements similar to condyloid joint (thumb)
ball and socket joint
allows the greatest range of motion (shoulders, hip joints)
knee joint
- largest and most complex joint in the body
- typical synovial joint
- most important structures in synovial joints are tendons, ligaments, cartilage and synovial fluid.
- Ligaments are well-defined, fibrous bands that connect the articulating bones.
- designed to assist the joint capsule to maintain stability in the joint by restraining excessive movement, but can also control the degree and direction of movement that occurs.
- have no blood supply
Tendons
- tough, inelastic cords of tissue that attach muscle to bone
- have blood supply
- Joints are further strengthened by muscle tendons that extend across the joint and assist ligaments to hold the joint closed.
- Tendons and muscles work together and can only exert a pulling force.
synovial fluid
Secretion of synovial membranes that lubricates joints and nourishes articular cartilage
hyaline cartilage
- limited blood supply but receives nourishment via the synovial fluid.
- thicker in the leg joints, where there is greater weight bearing
Flexion
bending a joint
extension
Straightening of a joint
rotation
CIRCULAR MOVEMENT AROUND AN AXIS
Elevation
raising a body part
Depression
lowering a body part
Abduction
Movement away from the midline of the body
Adduction
Movement toward the midline of the body
dorsi flexion and plantar flexion
-foot
-pointing of toes upward or downward
Circumduction
circular movement of a body part
Pronation
turning the palm downward
Supination
movement that turns the palm up
Protraction
Moving a part forward
Retraction
moving a part backward
skeletal muscle
- only voluntary muscle- controlled consciously
- every action requires skeletal muscle
- Function= contract to move parts of the body that muscle is attached
- most SM are attached to 2 bone across joint-muscle brings bone closer together
Sm form long straight multinucleated fibres
smooth muscle
- found inside stomach, intestine, blood vessel
- weakest of all muscles, makes organs contract to move substances through the organ
- controlled by unconsious part of brain= involuntary
- SV= smooth- contrast to sm and cm
cardiac muscle
- responsible for pumping blood throughout body (found in heart)
- cannot be controlled consciously= involuntary muscle
- brain stimulates itself to contract
- cardiac muscle= striated
