Appendicular Skeleton Flashcards
How is the appendicular skeleton made up oh
Of all the bones of the limbs, together with the bony girdles that anchor them to the axial skeleton
What parts are included in the appendicular girdle
- pectoral girdle
- upper limbs
- pelvic girdle
- lower limbs
what is the pectoral girdle made up of
- clavicle
* scapula
elaborate of the clavicle
- It is the collar bone, a long slender S-shaped bone
- One end articulates with the sternum and the other end with the acromium of the scapula.
THIS IS THE ONLY ATTACHMENT OF THE PECTORAL GIRDLE TO THE AXIAL SKELETON
Elaborate on the scapula
• the shoulder blade, a triangular bone
NOT ATTACHED TO THE AXIAL SKELETON
• but moves over the ribs at the back (posteriorly)
How many bones make up the upper limb
30 separate bones
Explain how the upper arm is made up
- it’s made up of a typical long bone (the humerus)
- The head of the humerus fits into the glenoid cavity of the scapula at the shoulder (forming a ball and socket joint)
- The forearm is made up of the two parallel long bones, the radius and ulna
what do the ulna and radius articulate more with
Ulna with the humerus
Radius with the carpal bones
why is it easy to dislocate a shoulder
The upper arm has extreme mobility due to the shallow ball and socket joint (glenoid cavity) and the only clavicle is attached to the axial skeleton, whereas the scapula that is not attached to the axial skeleton can move quite freely across the thorax, allowing the arm to move with it
LABEL THE UPPER LIMP
PAGE 56
How is the hand made up
• of 27 bones which are divided into three groups
- the carpals (in the wrist)
- the metacarpals (in the palm)
- the phalanges (in the fingers and thumb)
During childhood and adulthood how does the pelvic girdle change
during childhood the pelvic girdle is made up of three bones:
- the ilium (the hip bone)
- the ischium (the sitting bone)
- the pubis (the two bones which join in the front by means of punic symphysis)
in adulthood these bones became fused for strength and are then called the focal bones, although the may still be referred to by their individual names
What are the functions of the pelvic girdle
- to attach the lower limbs to the axial skeleton
- To transmit the weight of the upperbody to the lower limbs
- To support and protect the organs with in the pelvic area
- To provide attachment points for the muscles that move the lower limbs
How is the pelvic girdle attached to the axial skeleton
It is attached by some of the strongest ligaments in the body which forms a very secure and strong base for the articulation of the legs
How is the hip joint formed
by the head of the femur articulating within a deep, cup-like socket, called the acetabulum (formed at the point of fusion between the three hip bones)
LABEL THE DIAGRAM OF A PELVIC GIRDLE
PAGE 58 & 59
Why are the bones of the lower limbs so thick and strong
They carry the weight of the whole erect body
Describe the different bones found in the lower limbs
- The femur - this makes up the thigh, it is the longest, largest and strongest bone in the body (it connects to the pelvic girdle at the hip joint which is a ball and socket joint)
- The tibia & fibula - these make up the lower part of the leg, they are two parallel long bones.
- tibia - is larger and articulates with the femur to form the knee joint, it also articulated with a large tarsal bone (talus) at the ankle
- fibula - does not form part of the knee joint and merely helps to stabilize the ankle joint
How is the foot made up
• by 26 bones which are divided into three groups:
- the tarsals (the ankle)
- the metatarsals (the body of the foot) m3. the phalanges (the toes)
LABEL THE DIAGRAM OF THE PELVIC GIRDLE AND LOWER LIMB
PAGE 57
Give examples of diseases of the skeletal system
- rickets (in children, is the result of the body’s inability to absorb calcium salts due to a lack of vitamin D)
- osteomalacia (the same thing as rickets but in adults)
- OSTEOPOROSIS
Why are calcium salts important
- Calcium is the mineral needed to build strong and hard bones in children
- lower levels of calcium in the blood result in his element being withdrawn from the bones, as a result the bones become soft and weak and unable to support the weight of the body
What are some signs and symptoms of rickets
- skeletal deformities (malformed skull, bowed legs, knock knees, abnormal curvature of the spine, pelvic deformities)
- stunted growth
- dental problems (eg. poor enamel)
What is the difference between osteoporosis and osteomalacia
osteomalacia results from a defect in the bone-building process whereas osteoporosis develops because of a weakening of previously constructed bone
