ppt lesson 5.1 functions and organization of the skeletal system

what are the 4 functions of the skeletal system?

• support & movement

• protection

• storage

• manufacturing

explain how the skeleton supports as a function

• supports the body, soft tissues, organs, and body walls

• holds us up

• tendons-

  • connect muscle → bone

  • anchorage of skeletal muscles

  • needed for movement

• ligaments-

  • connect bones → bones at joints

  • stability of joints

explain how the skeleton protects as a function, and what 3 parts of the skeleton protects what organs

• the skeleton surrounds vital organs

  • skull → brain

  • vertebrae → spinal cord

  • ribs → heart and lungs

what are the 2 classifications of the skeleton?

axial and appendicular

what is the axial skeleton comprised of?

• makes up the central axis of the body-

  • skull

  • vertebrae

  • rib cage

• primarily protection functions

what is the appendicular skeleton comprised of, and what are the upper and lower limbs?

• makes up the limbs/appendages

• upper limbs-

  • shoulders

  • arms

• lower limbs-

  • pelvis

  • legs

• primarily support & movement functions

explain the relationships between yellow & red bone marrow to fat storage & blood cell formation

• yellow marrow-

  • adipose tissue

  • fat storage

• red marrow-

  • blood cell formation/hematopoiesis occurs

  • RBCs, WBCs, & platelets are produced here

explain how the skeleton stores minerals

• the skeleton stores minerals, especially calcium & phosphorous

• ca and p-

  • incorporated into bone tissue

  • released back into the bloodstream to maintain physiological processes levels

explain calcium homeostasis

• calcium is required for muscle contraction and bone growth & remodeling

• calcium homeostasis-

  • the skeleton maintains stable calcium levels in the blood

  • inadequate calcium supply-

    • parathyroid hormone PTH activates osteoclasts-

      • breaks down bone

      • releases calcium into the bloodstream

    • calcitonin activates osteoblasts that builds bones

what are the 4 classifications by shape of bones?

• long

• short

• flat

• irregular

what are long bones and examples of them?

• longer than wide

• ends flared for use at a joint

• functions as levers, move when muscles contract

• examples-

  • clavicle

  • humerus

  • radius

  • ulna

  • metacarpus

  • phalanges

  • femur

  • tibia

  • fibula

  • metarsus

what are short bones and examples of them?

• cube-like and squarish shape

• equal in length, width, thickness

• stability, support, limited motion

• examples-

  • wrist, ankle, knee/patella bones

which bone in the body is a sesamoid bone and why?

patella due to its shape, embedded in tendons / not directly connected to other bones

what are flat bones and examples of them?

• thin, flat, curved

• unique shapes to fit functions-

  • points of attachment for muscles

  • protect internal organs

• examples-

  • cranial/skull

  • scapula/shoulder

  • sternum/breastbone

  • ribs

  • pelvis bones

what are irregular bones and examples of them?

• complex and oddly shaped

• structure fits function

• examples-

  • vertebrae for spinal cord

  • facial bones like ones containing sinuses

what are sesamoid bones and examples of them?

• small and round

• embedded in tendons

• function: protect tendons from compressive forces

• examples-

  • in tendons associated with the feet, hands, knees

  • patella