Terms Ch. 3 The Skeletal System

fontanelles

aka: soft spots, normally present on the skull of a newborn; facilitate the passage through the birth canal; allow for growth of the school during the first year

fibrous joints

aka: sutures, consisting of inflexible layers of dense connective tissue, hold the bones tightly together; do not allow for movement in adults, some do allow for movement in newborns and young children

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

allow only slight movement and consist of bones connected entirely by cartilage. (ex. where the ribs connect to the sternum (breast bone)-allow movement for breathing)

acromion

an extension of the scapula that forms the high point of the shoulder

foramen (plural = foramina)

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

talus

anklebone that articulates with the tibia and fibula

ligaments

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

humerus (pl.-humeri)

bone of the upper arm

functions of the skeletal system

bones act as framework; bones support and protect the internal organs; joints work in conjunction with muscles, ligaments, and tendons, making possible the wide variety of body movements; calcium stored in bones, which is required for normal nerve and muscle function; red bone marrow, which has an important function in the formation of blood cells, is located within spongy bone.

sphenoid bone (SFEE-noid)

bones of the cranium that forms part of the base of the skull and parts of the floor and sides of the orbits (bony socket that surrounds and protect the eyeball)

phalanges (toes)

bones of the toes; great toe has 2 phalanges; each of the other toes have 3

carpals

bones that form the wrist

body of the sternum

bony structure that forms the middle portion of the sternum

manubrium

bony structure that forms the upper portion of the sternum

ilium

broad blade-shaped bone that forms the back and sides of the pubic bone

pubic symphysis

cartilaginous joint that allows some movement to facilitate childbirth; located between pubic bones in the anterior of the pelvis

yellow bone marrow

functions as a fat storage area, composed chiefly of fat cells and is located in the medullary cavity

spongy bone

lighter, and not as strong, as compact bone; commonly found in the ends and inner portions of long bones such; red bone marrow located here.

synovial membrane

lines the capsule and secretes synovial fluid

medullary cavity

located in the shaft of a long bone and is surrounded by compact bone.

external auditory meatus (mee-AY-tus)

located in the temporal bone on each side of the skull, is the opening of the external auditory canal of the outer ear

red bone marrow

located within the spongy bone, is hemopoietic tissue that manufactures red blood cells, hemoglobin, white blood cells and thrombocytes.

intervertebral disks

made of cartilage, separate and cushion the vertebrae from each other; act as shock absorbers and allow for movement of the spinal column

cruciate ligaments (KRRO-shee-ayt)

make possible the movement of the knee

appendicular skeleton

makes body movement possible and protects the organs of digestion, excretion, and reproduction; consists of 126 bone that are organized into the upper extremities (shoulders, arms, forearms, wrists, and hands) and lower extremities (hips, thighs, legs, ankles, and feet)

scapula (plural-scapulae)

shoulder blade

pectoral girdle

shoulders form this, which supports the arms and hands; aka shoulder girdle (girdle-structure that encircles the body

vertebrae

single segment of the spinal column; 26 make up the spinal column; bony structure units of the spinal column.

sacrum (SAY-krum)

slightly curved, triangular-shaped bone near the base of the spine that forms the lower portion of the back (25th vertebrae)

radius

smaller and shorter bone in the forearm; runs up the thumb side of the arm

fibula

smaller of the two bones of the lower leg

cartilage

smooth, rubbery, blue-white connective tissue that acts as a shock absorber between bones

components of synovial joints

synovial capsule synovial membrane synovial fluid ligaments bursa

ball and socket joints

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

hinge joints

synovial joint such as knees and elbows, allow movement primarily in one direction or plane

mastoid process

the bony projection located on temporal bones just behind the ears.

cervical vertebrae

the first set of 7 vertebrae that form the neck; know as C1-C7

bone

the form of connective tissue that is the second hardest tissue in the human body, behind dental enamel; capable of healing, growth and reshaping itself.

pubic bones

the ileum, ischium, and pubis are seperate at birth, but fuse to form the left and right __________, which are held together by the pubic symphysis.

epiphysis

wide end of a long bone that is covered with articular cartilage

occipital bone

forms the posterior floor and walls of the cranium

appendicular

referring to an appendage, which is anything that is attached to a major part of the body

popliteal (pop-LIT-ee-al)

refers to the posterior space behind the knee where the ligaments, vessels, and muscles related to this joint are located

lumbar

relating to the part of the back between the ribs and pelvis

malleolus (mal-LEE-oh-lus) (pl. malleoli)

rounded bony protuberance on each side of the ankle

thoracic vertebrae

second set of 12 vertebrae; form the outward curve of the spine; known as T1-T12

ribs

12 pairs, aka costals, attach posteriorly to the thoracic vertebrae

phalanges (s-phalanx)

14 bones of the fingers (and toes); each of the 4 fingers has 3 bones-distal, middle, and proximal phalanges; thumb has 2 bones-distal and proximal.

inferior conchae (KONG-kee or KONG-kay) (sing. = concha)

2 bones of the face that are thin, scroll-like bones that form part of the interior of the nose

zygomatic bones

2 bones of the face that articulate with the frontal bone; aka; cheekbones

maxillary bones

2 bones of the face that form most of the upper jaw; aka: maxilla; singular maxilla

palatine bones

2 bones of the face that form part of the hard palate of the mouth and the floor of the nose

nasal bones

2 bones of the face that form the upper part of the bridge of the nose

lacrimal bones

2 bones of the face that make up part of the orbit of the inner angle of the eye

parietal bones

2 bones that form most of the roof and upper sides of the cranium

temporal bones

2 bones that form the sides and base of the cranium

metatarsals

5 bones that form part of the foot to which the toes are attached

metacarpals

5 bones that form the palm of the hand

auditory ossicles (OSS-ih-kulz)

6 tiny bones of the middle ear

tarsal

7 bones that make up the ankle

coccyx (KOCK-sicks)

aka tailbone, forms the end of the spine and is actually make up of 4 small vertebrae that are fused together (26th vertebrae)

spinal column

aka vertebal column, supports the head and body, and protects the spinal cord

olecranon process (ol-LEK-rah-non)

aka funny bone; large projection on the upper end of the ulna; forms point of the elbow and exposes a nerve that tingles when struck

calcaneus

aka heel bone, largest of the tarsal bones

joints

aka: articulations, the place of union between two or more bones

acetabulum (ass-eh-TAB-you-lum)

aka hip socket, the large circular cavity in each side of the pelvis that articulates with the head of the femur for form the hip joint

mandible

aka jawbone, only movable bone of the skull

patella

aka kneecap; bony anterior portion of the knee

pelvic girdle

aka pelvis or hips; protects internal organs and supports the lower extremities; a cup-shaped ring of bone at the lower end of the trunk that consists of the ilium, ischium, and pubis.

thoracic cavity

aka rib cage; bony structure that protects the heart and lungs; includes ribs, sternum, and upper portion of the spinal column extending from the neck to the diaphragm, not including the arms.

tibia

aka shinbone, larger weight-bearing bone in the anterior of the lower leg

temporomandibular joint

aka TMJ; mandible attached to the skull at this location

sternum

aka breastbone, forms the middle of the front of the rib cage and is divided into three parts: manubrium body of the sternum xiphoid process

clavicle

aka collar bone, slender bone that connects the manubrium of the sternum to the scapula (bones of the shoulder)

knees

complex joints that make possible movement between the upper and lower leg

skull

consists of 8 bones that form the cranium, 14 bones that form the face, and 6 bones that form the middle ear

skeletal system

consists of: bones bone marrow cartilage joints ligaments synovial membrane synovial fluid bursa

articular cartilage

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.

synovial joints

created where two bones articulate (come together) to permit a variety of motions

meniscus

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

compact bone

dense, hard, and very strong bone that forms the protective outer layer of bones

ischium (ISS-kee-um)

forms the lower posterior portion of the pubic bone, bears the weight of the body when sitting

meatus

external opening of a canal

vomer bone

facial bone that forms the base for the nasal septum (cartilage wall that divides the 2 nasal cavities

bursa (plural = bursae)

fibrous sac that acts as a cushion to ease movement in areas that are subject to friction

true ribs

first seven pairs of ribs attached anteriorly to the sternum

synovial fluid

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

ankles

form the joint between the lower leg and the food are made up of 7 short tarsal bones

ethmoid bone

forms part of the posterior portion of the nose, the orbit, and the floor of the cranium

pubis

forms the anterior portion of the pubic bone, is located below the urinary bladder

ulna

larger and longer bone of the forearm; proximal end of the ulna articulates with the distal end of the humerus to form the elbow joint

floating ribs

last 2 pairs of ribs attached posteriorly

false ribs

next three pairs of ribs attached anteriorly to cartilage that joins with the sternum

process

normal projection on the surface of a bone that serves as an attachment for muscles and tendons

synovial capsule

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

frontal bone

part of the cranium that forms the forehead

axial

pertaining to an axis, which is an imaginary line that runs lengthwise through the center of the body

hemopoietic (hee-moh-poy-ET-ick) or hematopoietic

pertaining to the formation of blood cells

medullary

pertaining to the inner section

cervical

pertaining to the neck

cranium

portion of the skull that encloses the brain, made up of 8 bones

axial skeleton

protects the major organs of the nervous, respiratory, and circulatory systems; consists of 80 bones including those of the skull, ribs, sternum, and thoracic vertebrae of the thoracic cavity, and other vertebrae of the spinal column

diaphysis

the shaft of a long bone

sacroiliac

the slightly movable articulation between the sacrum and posterior portion of the ilium

xiphoid process

the structure made of cartilage that forms the lower portion of the sternum

lumbar vertebrae

third set of 5 vertebrae and form the inward curve of the lower spine; known as L1-L5

endosteum

tissue that lines the medullary cavity

periosteum

tough, fibrous tissue that forms the outermost covering of bone

femur

upper leg bone; largest bone in the body; aka thigh bone