muscular and skeletal systems Flashcards
function of animmal skeletal systms
physical support and locomotion
muscular systm main dunction
generaters force
endoskleton
serves as framwork within all vertebrate organisms
muscles are attached to bones, permitting movement
th endoskeleton also provides protection by surrounding delicate internal organs with bone
the rib cage protects thoracic organs (heat and lungs), skull and vertebral column protect brain and spinal cord
2 major components of skeleton are cartilage and bone
cartilage
a type of connective tissue that is softer and more flexible than bone
retained in adults where firmness and flexibility is needed
ex: ear, nose, walls of larynx and trachea, skletal joints contain cartilage
chrondrocytes
cells responsible for synthesizing cartilage
bone
mineralized connective tissue that has ability to withstand physical stress
adapted for body support, bone tissue is hard, and also elastic and lightweight
2 basic types: compact bone and spongy bone
compact bone
dense bone that does not appear to have an cavities when observed with naked eye
the bony matrix id deposited in structural units called osteons
each osteon has a central microscopic channel called Haversian canal surrounded by a number of concntric circles of bony matrix (calcium phosphate) called lamellae
osteon
the bony matrix is deposited in structural units called osteons (Haversian systems)
each osteon has a central microscopic channel called a Haversian canal, surrounded by cencentric circles of bony matrix (calcium phosphat) called lamellae
spongy bone
much less dense than compact bone, and consists of an interconnecting lattice of bony spicules (hard body)
the cavities between the spicules are filled with yellow or red bone marroe
yellow bone marrow
inactive and infiltrated by adipose tissue
fills the cavities between spicules of spongy bone
red bone marrow
involved in blood cell formation
fills the cavities between spicules of spongy bone
the 2 types of cells found in bone tissue
osteoblasts and osteoclasts
osteoblasts
1 of 2 type of cells found in bone tissue
synthesize and secrete the organic constituents of the bone matrix
once they have become surrounded by their matrix they mature into osteocytes
osteocytes
made of mature osteoblasts
osteoclasts
1 of 2 types of cells in bone tissue
are large, multinucleated cells involved in bone reabsorption when bone is broken down and minerals are released into blood
axial skeleton
is the basic framework of the body
consisting of the skull, vertebral column and rib cage
it is the point of attachment of the appendicular skeleton (includes bones of the appendages (limbs) anf the pectoral girdles (connect to arm) and pelvic girdles
appendicular skeleton
includes the bones of the appendages (limbs) and the pectoral and pelvic girdles
how are these bones held together:
- sbones of the skull
- bones that move relative to one another
sutures or immovable joints hold the bones of the skull together
bones that move relative to one another are held together by movable joints and are supported and strengthened by ligaments
ligaments
serve as bone-to-bone connectors
tendons
attach skeletal muscle to bones and bend the skeleton at the movable joints
origin
point of attachment of a muscle to a stationary bone
(proximal end) in limb muscles
insertion
attachment of a muscle to the bone that moves (distal end in limb muscles) is called the insertion
extension and flexion
indicates a straightening of a joint, whereas flexion refers to a bending of a joint
the 3 types of muscle
skeletal muscle
smooth muscle
cardiac muscle