Med Term Skeletal

Bones combining forms

oss/e, oss/i, oste/o, ost/o

Bones function

Act as the framework for the body, protect the internal organs, and store calcium.

Bone Marrow combining forms

myel/o (also means spinal cord)

Bone marrow function

Red one helps form red blood cells. Yellow one stores fat.

Cartilage combining forms

chondr/o

Cartilage function

Creates a smooth surface for motion within the joints and protects the ends of the bones.

Joints combining forms

arthr/o

Joints function

Work with the muscles, ligaments, and tendones to make a variety of motions possible.

Ligaments combining forms

ligament/o

Ligament function

Connect one bone to another.

Synovial Membrane combining forms

synovi/o, synov/o

Synovial membrane function

Forms the lining of synovial joints and secretes synovial fluid.

Synovial Fluid combining forms

synovi/o, synov/o

Synovial fluid function

Lubricant that makes smooth joint movements possible.

Bursa combining forms

burs/o

Bursa function

Cushions areas subject to friction during movement.

ankyl/o

crooked, bent, stiff

arthr/o

joint

burs/o

bursa

chondr/i, chondr/o

cartilage

cost/o

rib

crani/o

skull

-desis

to bind, tie together

kyph/o

bent, hump

lord/o

curve, swayback, bent

Lumb/o

lumbar, lower back

myel/o

spinal cord, bone marrow

oss/e, oss/i, ost/o, oste/o

bone

scoli/o

curved, bent

spondyl/o

vertebrae, vertebral column, backbone

synovi/o, synov/o

synovial membrane, synovial fluid

skeletal system consists of

bones, bone marrow, cartilage, joints, ligaments, synovial membranes, synovial fluid, and bursae

Calcium

mineral required for normal nerve and muscle function, is stored in bones.

Where is red bone marrow located

spongy bone

Ossification (oss-uh-fih-KAY-shun)

newborn's skeleton begins as fragile membranes and cartilage, but after three months it starts turning into bone (continues into adolescence)

How does bone formation continue after growth is completed

osteoclast cells break down old or damaged bone and osteoblast cells help rebuild the bone

Ossification repairs

minor damage to the skeletal system that occurs during normal activity and also repairs bones after injuries such as fractures.

Bone is what kind of tissue

connective, is the second hardest tissue in the human body behind dental enamel

Periosteum (pehr-ee-OSS-tee-um)

the tough, fibrous tissue that forms the outermost covering of bone (peri- means surrounding, oste means bone, and -um is a noun ending)

Compact bone

also known as cortical bone, is the dense, hard, and very strong bone that forms the protective outer layer of bones.

Spongy bone

also known as cancellous bone, is porous ("sponge-like"), which makes it lighter and weaker than compact bone

Red bone marrow

often located in spongy bone, which is commonly found in the ends and inner portions of long bones as well as in the pelvic bones, ribs, and the vertebrae of the spinal column

long bones

major bones of the arms and legs, including the femur and humerus

Short bones

include the bones of the wrist and ankle, roughly cube-shaped, and are made up of spongy bone covered with a layer of compact bone.

medullary cavity (MED-you-lehr-ee)

the central cavity located in the shaft of long bones, where it is surrounded by compact bone, here red and yellow bone marrow are stored.

Medullary means

pertaining to the inner section.

endosteum (en-DOS-tee-um)

the tissue that lines the medullary cavity (end- means within, oste means bone, and -um is a noun ending)

Red bone marrow

a hematopoietic tissue that manufactures red blood cells, hemoglobin, white blood cells, and thrombocytes

Hematopoietic (hee-MAH-toh-poy-et-ick)

means pertaining to the formation of blood cells (hemat/o means blood, and -poietic means pertaining to formation

Yellow bone marrow is composed chiefly of

fat cells and is located in the medullary cavity of long bones

How much red bone marrow is changed to yellow from birth to adolescence

about half

Cartilage (KAR-tih-lidj)

the smooth, rubbery, blue-white connective tissue that acts as a shock absorber between bones, makes up the flexible parts of the skeleton such as the outer ear and the tip of the nose

Articular cartilage (ar-TICK-you-lar KAR-tih-lidj)

covers the surfaces of bones where they come together to form joints; makes smooth joint movement possible and protects the bones from rubbing against each other

meniscus (meh-NIS-kus)

the curved, fibrous cartilage found in some joints, such as the knee and the temporomandibular joint of the jaw

diaphysis (dye-AF-ih-sis)

the shaft of a long bone

epiphyses (ep-PIF-ih-seez)

the wider ends of long bones such as the femurs of the legs

Each epiphysis is covered with

articular cartilage to protect it

proximal epiphysis

the end of the bone located nearest to the midline of the body.

distal epiphysis

the end of the bone located farthest away from the midline of the body.

foramen (foh-RAY-men)

an opening in a bone through which blood vessels, nerves, and ligaments pass

process

a normal projection on the surface of a bone that most commonly serves as an attachment for a muscle or tendon

Joints

also known as articulations, place of union between two or more bones

How are joints classified

according to their construction or based on the degree of movement they allow.

Fibrous joints

consists of inflexible layers of dense connective tissue, hold the bones tightly together

Fibrous joints in children vs. adults

these joints, which are also known as sutures, allow little or no movement. In newborns and very young children, some fibrous joints are movable before they have solidified

fontanelles (fon-tah-NELLS)

also known as the soft spots, normally present on the skull of a newborn to facilitate birth; allow for the growth of the skull during the first year

What happens to fontanelles with age

As the child matures, and the sutures close, and they gradually harden.

Cartilaginous joints (kar-tih-LADJ-ih-nus)

allow only slight movement and consist of bones connected entirely by cartilage

Example of cartilaginous joints

Where the ribs connect to the sternum (breast bone), these joints allow movement during breathing.

Example of cartilaginous joints

pubic symphysis (PEW-bick SIM-fih-sis) allows some movement to facilitate childbirth; joint is located between the pubic bones in the anterior (front) of the pelvis

synovial joint (sih-NOH-vee-al)

created where two bones articulate to permit a variety of motions

Ball-and-socket joints

such as the hips and shoulders, allow a wide range of movement in many directions (synovial joint)

Hinge joints

such as the knees and elbows, are synovial joints that allow movement primarily in one direction or plane

Synovial capsule

the outermost layer of strong fibrous tissue that resembles a sleeve as it surrounds the joint.

Synovial membrane

lines the capsule and secretes synovial fluid.

Synovial fluid

flows within the synovial cavity, acts as a lubricant to make the smooth movement of the joint possible.

Ligaments (LIG-ah-mentz)

bands of fibrous tissue that form joints by connecting one bone to another bone or by joining a bone to cartilage.

Bursa (BER-sah)

fibrous sac that acts as a cushion to ease movement in areas that are subject to friction, such as in the shoulder, elbow, and knee joints where a tendon passes over a bone.

The typical adult human skeleton consists of approximately how many bones

206

the skeleton is divided into the

axial and appendicular skeletal systems

Axial skeleton protects the

major organs of the nervous, respiratory, and circulatory systems.

In humans, the axial skeleton consists of how many bones

80 of the head and body that are organized into five parts (bones of the skull; the ossicles (bones) of the middle ear; the hyoid bone, located on the throat between the chin and the thyroid; the rib cage; and the vertebral column)

appendicular skeleton

makes body movement possible and also protects the organs of digestion, excretion, and reproduction.

How many bones are in the human appendicular skeleton

126 bones that are organized into the upper extremities (shoulders, arms, forearms, wrists, and hands) and the lower extremities (hips, thighs, legs, ankles, and feet).

appendage

anything that is attached to a major part of the body

appendicular

referring to an appendage.

extremity

the terminal end of a body part such as an arm or leg.

The skull consists of how many bones

8 bones that form the cranium, 14 bones that form the face, and 6 bones in the middle ear.

The cranium (KRAY-nee-um)

portion of the skull that encloses and protects the brain (crani means skull, and -um is a noun ending)

The cranial bones are joined by

jagged fibrous joints that are often referred to as sutures

Frontal bone

the anterior portion of the cranium that forms the forehead; houses the frontal sinuses and forms the roof of the ethmoid sinuses, the nose and part of the socket that protects the eyeball

parietal bones (pah-RYE-eh-tal)

two of the largest bones of the skull. Together they form most of the roof and upper sides of the cranium

occipital bone (ock-SIP-ih-tal)

forms the back part of the skull and the base of the cranium

temporal bones

form the sides and base of the cranium.

external auditory meatus (mee-AY-tus)

the opening of the external auditory canal of the outer ear; located within the temporal bone on each side of the skull.

meatus

the external opening of a canal.

sphenoid bone (SFEE-noid)

an irregular, wedge-shaped bone at the base of the skull. This bone makes contact with all of the other cranial bones and helps form the base of the cranium, the sides of the skull, and the floors and sides of the eye sockets

ethmoid bone (ETH-moid)

light, spongy bone located at the roof and sides of the nose. Here it separates the nasal cavity from the brain, and it also forms a portion of each orbit.

orbit

the bony socket that surrounds and protects each eyeball.

auditory ossicles (OSS-ih-kulz)

the three tiny bones located in each middle ear