Question | Answer |
function of the skeletal muscles | movement of bones, maintain posture, support, guard enterances/ exits, body temp |
skeletal muscle | only type that is voluntary |
myofibril | fibers inside a muscle cell |
epimysium | outermost tissue of muscle cell |
perimysium | 2nd layer of muscle cell; surrounds bundles of cells |
endomysium | surrounds muscle fiber |
components of a muscle cell | sarcoplasm, mitochondria, sarcoplasmic reticulum |
sarcoplasmic reticulum | stores calcium ions and releases them when needed |
sarcolemma | cell membrane of a muscle cell |
myosin | thick protein filaments that form the dark lines of a fibril |
actin | thin protein filament; forms the light lines of the fibril (i bands) |
sacromere | contractile unit of the muscle |
z disc | the zigzags on a fibril, made of actin; make the boundries |
action potential | message from neuron; produced by ach; electrical upsetting travelling completely around the muscle cell |
neuromuscular junction | where the axon terminal meets the muscle cell |
ach (acetycholine) | tells muscles to contract; released by neuron with use of Ca+2 and goes to muscle cell |
creatine phosphate | gives extra energy when atp is low; gives its phosphate to a ADP to make it ATP and usable |
aerobic respiration | slow but most efficient; Glucose + O2 =ATP; converts food to energy |
anaerobic respiration | when you work hard enough so O2 is not getting to tissue; very fast but no efficient. no O2 needed. |
flexion | decreases the angle of the joint; brings two bones closer together |
extension | increases the angle of the joint; two bones farther from eachother |
hyperextention | bending beyond 180* angle |
abduction | take/ move away from body |
adduction | move closer to body |
circumduction | movement in a circular motion (ball and socket joints) |
supination | palms up |
pronation | palms down |
organs of the skeletal system | bones, joints, cartilages, ligaments |
two subdivisions of the skeleton | axial and appendicular |
ligaments | connect bone to bone |
functions of bones | support the body, protection, levers, store minerals, blood cell formation |
classification of bones | long bones, short bones, flat bones, irregular bones |
long bone | compact bone, dense, longer than wide |
short bone | cube shaped, mostly spongy |
flat bone | flattened, thin, usually curved |
irregular bone | bones that don't fit in any other catergory |
epiphyseal | growing plate or line; determines growth; plate = cartilage and line = bone |
diaphysis and epiphysis | d = mostly compact, e = spongy |
two types of marrow | red and yellow |
red marrow | hematopheisis (production of blood) |
yellow marrow | where fat is stored; found in diaphysis |
perferating canals | move horizontally through bone |
central canals | move vertically through bones |
osteons | run the length of the bone |
3 types of muscle cells | osteocytes, osteoblasts, osteoclasts |
osteocytes | mature muscle cells |
bone remodeling | controlled building and breaking of bone; happens when calcium levels are to high or low |
calcium | involved in muscle contraction, sending nerve impulses, blood clotting |
collagen | protein that gives bone a flexible quality |