Chapter 6: Skeletal System Exam Review Flashcards
Appendicular Skeleton
arm bones, leg bones, pelvic and shoulder gridles
Axial Skeleton
skull, vertebrae, ribs
Articulation
aka joints
where bones connect to each other
sometimes points of movement
Bursa
sac of synovial membranes beneath tendons
Diaphysis
shaft along long bones
Epiphyseal
discs at the junction of diaphysis w/ each epiphysis
closure of discs means all of cartilage matrix of the discs have been replaced by bone matrix and growth in length stops
Epiphysis
ends of diaphysis
Fontanel
“soft spots”; incomplete ossification of the skull and are areas of fibrous connective tissue
Allows for brain to grow after birth and permits compression of the baby’s head to exit the birthing canal
Haversian system
osteons; microscopic cylinders of bone matrix w/ osteocytes in center
Ligament
connects bones together
Ossification
starts in middle of bone and replaces soft cartilage w/ compact bone
Osteoblast
produce bone cells
production of bone matrix is done by osteoblasts
Osteoclast
destroy bone cells
Paranasal sinus
air cavities in maxilla, frontal, sphenoid, and ethmoid bones
Periosteum
lines bone in areas not covered by articular cartilage
made of fibrous connective tissue
contains collagen that enters the bone itself
anchors the tendons that connect muscle to bone and the ligaments that connect bone to bone
Suture
in between cranial bones and are immovable articulations
Synthesis
the production of something
ex: protein synthesis
Synovial fluid
prevents friction in joint cavities
Red bone marrow
principal hematopoietic tissue that produces blood cells
Calcium
essential for blood clotting and bone structure and excess stored in bones
becomes part of the salts in the bone matrix
Skeleton
is framework the supports the body
attached is muscles that move the skeleton
protect internal organs from mechanical injury
Ex: skull protects brain; ribs protect heart, lungs, spleen; and vertebrae protect the spinal cord
Compact bone
made of Haversian systems, which are cylindrical arrangements of osteocytes within matrix
Spongy bone
contains osteocytes and bone matrix, but these are not arranged in Haversian systems
often contains red bone marrow
Osteocytes
bone cells
regulate the amount of calcium in the bone matrix
Bone matrix
made of calcium carbonate and calcium phosphate
Long bones
bones of the arms, legs, hands, and feet
Short bones
wrist and ankle bones
Flat bones
pelvic bone, cranial bone, ribs
Irregular bones
vertebrae, facial bones
Articular cartilage
provides a smooth surface for joints when moved
covers the joint surfaces of bones
Skeleton of Embryo
first formed by cartilage and fibrous connective tissue and is gradually replaced by bone in a process called ossification
cranial and facial bones are first made of fibrous connective tissue
ossification begins in the 3rd month of gestation when osteoblasts differentiate from fibroblasts in the centers of bones
Vitamin D
necessary for the absorption of calcium and phosphorus in the small intestine
Vitamin C
necessary for the process of bone formation
Vitamin A
necessary for the process of bone formation
Phosphorus
becomes part of the salts in the bone matrix
Protein
becomes part of the collagen in the bone matrix
Growth hormone
increases protein synthesis and the rate of mitosis of chondrocytes in cartilage
pituitary gland
Insulin
increases energy production from glucose
pancreas gland
Calcitonin
decreases the reabsorption of calcium from the bones
thyroid gland
lowers blood calcium level
Thyroxine
increases protein synthesis and energy production from all food types
thyroxine gland
Parathyroid hormone
decreases the reabsorption of calcium by the small intestine and kidneys
parathyroid gland
raises the blood calcium level
Estrogen or Testosterone
helps maintain a stable bone matrix and promotes closure of the epiphyses of long bones
ovaries or testes gland
causes bones to stop growing
Factors of height and bone growth
Heredity - height is a genetic characteristics that is regulated by genes inherited from mom and dad
Exercise/Stress - for bones, exercise or stress means bearing weight; without normal stress, bones will lose calcium faster than it is replaced; affected bones develop osteoporosis with brittle, weak bones thus allowing easier breakage/fractures to occur
Nutrition
Hormones
Chemical Communications
Ribs/rib cage
protects heart, lungs, liver, and spleen from mechanical injury
True ribs = 7
False ribs = 3
Floating ribs = 2
Skull
protects brain from mechanical injury
Ileum, ischium, pubic (pelvic gridle)
attaches legs to axial skeleton
Clavicle and scapula (shoulder gridle)
attaches arm to axial skeleton
Bones of Skull
Mandible - sockets for teeth
Maxilla - sockets for teeth, forms hard palate of mouth, contains paranasal sinuses
Temporal bone - contain external auditory meatus
Zygomatic - forms points of cheeks
Palatine - forms hard palate of mouth
Ethmoid - contains openings for olfactory nerves, forms nasal septum, contains paranasal sinuses
Vomer - forms nasal septum
Lacrimal bone - contains nasal lacrimal duct
Occipital - contains foramen magnum (which contains the spinal cord)
Sphenoid - protects pituitary gland (Sella tursiea), contains paranasal sinuses
Nasal bones - forms bridge of the nose
Frontal - contains paranasal sinuses
Functions of paranasal sinuses
lighten weight of bones and resonance for voice
Sutures
Squamosal = temporal + parietal bones Lambdoidal = occipital + parietal bones Coronal = frontal + parietal bones
Auditory bones
malleus (mallet/hammer), incus (anvil), stapes (stirrup)
Functions of vertebral column
support trunk and head and to protect the spinal cord from mechanical injury
Vertebrae
Cervical = 7 (first is called atlas and second is called axis)
Thoracic = 12
Lumbar = 5
Sacral = 5 (fuse into one bone called sacrum, two hip bones articulate with the sacrum)
Coccygeal = 4-5 (fuse into one bone called the coccyx)
Supportive part called body
Bodies adjacent to vertebrae are separated by discs of cartilage (discs meant to absorb shock and permit slight movement)
Joints between vertebrae called symphysis joints
Scapula
forms shoulder gridle with clavicle and forms the socket for the humerus
Clavicle
articulates medially w/ manubrium of sternum and laterally w/ scapula
Synovial Joint Parts
Articular cartilage - provides smooth surface on the joint surfaces of the bones
Joint capsule - made of fibrous connective tissue; encloses the joint like a sleeve
Synovial membrane - lines the joint capsule and secretes synovial fluid
Synovial fluid - prevents friction within the joint cavity
Bursae - sacs of synovial fluid that permit tendons to slide easily across the joint
