Exam 3 Flashcards
long bones
longer than they are wide; forearm and femur
what is bone
an organ
short bones
cubelike with roughly equal lengths and widths; wrist and ankle
zygomatic bone
cheek bone; irregular bone
flat bones
thin, flattened, and usually curved; vertebrae and scapulae
how do bones grow
the cartilage in bones grow & over time, it slowly gets replaced by bone w/ the help of calcium (ossification); layer upon layer of calcium and phosphate salts begin to accumulate on cartilage cells
irregular bones
variety of shapes and are usually connected to several other bones; vertebrae and facial bones
pituitary dwarfism
lack of growth hormone, normal proportions with short stature; decrease in rate of cell division of cartilage cells in epiphyseal plate
sesamoid bones
usually small and nodular; patella
intramembranous bones
originate within sheetlike layers of connective tissues; broad, flat bones of the skull
presence of epiphyseal plate indicates
you’re not done growing
functions of bone (5)
support, protection, movement, storage, blood cell formation
long bone - epiphysis
on each end of a long bone; distal is farthest from the torso and proximal is closest to the torso
at what age is the human skeleton completely ossified
25
long bone - diaphysis
shaft of a long bone
what does exercise do for your bones
thicken and strengthen
function of red bone marrow
blood cell formation
long bone - articular cartilage
hyaline covering ends of epiphyses
long bone - periosteum
dense fibrous membrane covering surface of bones
function of yellow blood marrow
stores fat
long bone - medullary cavity
hollow chamber inside bone
another name for joints
articulations
myofibrils are composed of
myofilaments (proteins); actin and myosin
long bone - endosteum
lines the medullary cavity
long bone - bone marrow
connective tissue filling the medullary cavity
what gives skeletal muscles their striations
sarcomeres
compact bone - osteon
formed from osteocytes and extracellular matrix around a central canal
muscle strains are due to
ruptured blood vessels
compact bone - central canal
contains blood vessels and nerves surrounded by loose connective tissue; blood nourishes bone cells; extend longitudinally through bone tissue
tendons vs. aponeuroses
tendons are attached to bones; aponeuroses are (broad white sheets) attached to muscles or bones
compact bone - perforating canal (volkmann’s canal)
contains large blood vessels and nerves
what are muscle fibers
collections of sarcomeres
spongy bone (cancellous bone)
made of osteocytes and extracellular matrix; do not have central canals; have trabeculae
neuromuscular junction function
acetylcholine is released which causes the muscle fiber to contract; contractions
sliding filament theory
actin slides over myosin
osteocytes
mature bone cells found in lacunae
osteoblasts
bone forming cells
muscle atrophy
lack of muscle activity; reduces muscle size, tone, and power
osteoclasts
cells that erode bone
anatomy of cardiac muscle
branching muscle fibers joined together by intercalated discs; striated; involuntary
vitamin a deficiency
retards bone development
muscles of face used for
mastication; chewing
vitamin c deficiency
fragile bones
temporomandibular joint syndrome and cause
pain in the jaw (causing a lack of movement); injury to teeth/jaw, misalignment of teeth/jaw, teeth grinding, gum chewing, arthitis
vitamin d deficiency
rickets and osteomalacia
endochondral ossification
bone forms by replacing hyaline cartilage; most bones of the skeleton
epiphyseal plate
cartilage found at the end of long bones; separates epiphysis and diaphysis; growth plate
axial skeleton
cranium & facial bones (skull), sternum, rib cage, vertebral column
appendicular skeleton
all bones in arms and legs, clavicle, scapulae, pelvic girdle
height decreases at age
30
fibrous joints
dense connective tissue b/w bones; b/w bones in close contact
fibrous - syndesmosis
sheet connecting bone; b/w tibia and fibula
fibrous - suture
b/w flat bones; teeth-like projections with a thin layer of connective tissue; skull
fibrous - gomphosis
cone-shaped bony process in a socket; tooth in jawbone
cartilaginous joints
hyaline cartilage or fibrocartilage connect bones
cartilaginous - synchondrosis
bands of hyaline cartilage connect bones; some are temporary (epiphyseal plate); some are permanent (b/w manubrium & 1st rib, sternum & ribs 2-7)
cartilaginous - symphysis
pad of fibrocartilage b/w bones; pubic symphysis & joint b/w adjacent vertebrae
synovial joints
most joints & most complex; allow free movement
synovial parts - articular cartilage
resists wear & minimizes friction
synovial parts - joint cavity
filled w/ synovial fluid
synovial parts - joint capsule
two distinct layers; holds together bones of the joint
synovial parts - ligaments
reinforce the joint capsule and help bind the ends of bones
synovial parts - synovial membrane
inner layer of the joint capsule; encloses the synovial cavity which contains the synovial fluid
synovial parts - synovial fluid
clear fluid that lubricates joint; supplies cartilage with nutrients from blood vessels of the synovial membrane
meniscus (also part of synovial)
disc of fibrocartilage; cushion and help distribute body weight
synovial - ball & socket
spheroidal joint; widest range of movement; hip and shoulder
synovial - condylar
ellipsoidal joint; variety of movement except rotational; metacarpals and phalanges
synovial - gliding
plane joint; nearly flat; allows sliding back and forth and twisting movements; wrists and ankles
synovial - hinge
allows movement in only one direction; elbow
synovial - pivot
trochoid joint; movement limited to rotation around axis; neck
synovial - saddle
sellar joint; surface of one bone fits the complementary surface of another bone; carpal and metacarpal of thumb
abduction/adduction
movement away from and toward the body (respectively)
supination/pronation
palm up to palm down
dorsiflexion/plantar flexion
up and down movement of the foot
shoulder joint ligaments
coracohumeral, glenohumeral, transverse humeral
elbow joint ligaments
radial collateral and ulnar collateral
hip joint ligaments
iliofemoral, pubofemoral, ischiofemoral
knee joint ligaments
patellar, oblique popliteal, arcuate popliteal, tibial collateral, fibular collateral, cruciate ligaments in joint capsule
osteoarthritis
mechanical wear and tear of joints
rheumatoid arthritis
body’s immune system attacks the joints
functions of muscle
produce movement, maintain posture, stabilize joints, generate heat
skeletal muscle anatomy
made of skeletal muscle tissue, nervous tissue, blood, connective tissue; striated; voluntary; separated by fascia (covering); epimysium surrounds muscle under fascia; perimysium separates tissues into bundles (fascicles); endomysium separates muscle fibers in fascicles
skeletal muscle terms
muscle fiber - single muscle cell
muscle cell membrane - sarcolemma
sarcoplasm - muscle cell cytoplasm
myofilaments - actin (thin) or myosin (thicc)
sarcomeres
unit of muscle contraction
aponeurosis
broad, white sheet of tissue that acts as a tendon to attach muscles or bone
what delivers neurotransmitters to muscles and how
motor neuron; an electrical impulse triggers the release of neurotransmitters from the axon into the synapse. the neurotransmitters cross the synapse and bind to receptors. Receptors are located on the dendrites, and they receive and process the message
how does skeletal muscle relaxation work
when nerve impulses cease, two events relax the muscle fiber: 1) acetylcholinesterase - enzyme that rapidly decomposes remaining Ach in the synapse & the muscle impulse stops 2) when Ach breaks down, stimulus to sarcolemma and muscle fiber membrane ceases & the muscle fiber relaxes
motor unit
a motor neuron and all the muscle cells/fibers it stimulates
smooth muscle vs. cardiac muscle vs. skeletal muscle
smooth muscle: walls of organs, blood vessels, skin
- involuntary and not striated
cardiac muscle: wall of heart
- involuntary and striated
skeletal muscle: usually attached to bones
- voluntary and striated
movable end of muscle
insertion
prime mover
muscle primarily responsible for movement
what other muscles ASSISTS the prime mover
synergists; antagonists RESIST the prime mover’s actions
main myofibrils in muscle tissue
actin (thin)
myosin (thick)
bursae (also part of synovial)
synovial fluid-filled sacs; cushion and aid movement of tendons
