Ch. 5 Structure and Function

Acetabulum

Cup-shaped depression in the hip bone into which the top of the femur fits

Acromion

Part of the scapula that connects to the clavicle

Amphiarthrosis

Cartilaginous joint having some movement at the union of two bones

Ankle

Hinged area between the lower leg bones and the bones of the foot

Articular cartilage

Cartilage at a joint

Articulation

Point at which two bones join together to allow movement

Atlas

First cervical vertebra

Axis

Second cervical vertebra

Bone

Hard connective tissue that forms the skeleton of the body

Bone head

Upper, rounded end of a bone

Bone phagocyte

Bone cell that ingests dead bone and bone debris

Bursa

Sac lined with a synovial membrane that fills the spaces between tendons and joints

Calcaneus

Heel bone

Calcium

Mineral important in the formation of bone

Cancellous bone

Spongy bone with a lattice-like structure

Cardiac muscle

Striated involuntary muscle of the heart

Carpus, carpal bone

Wrist; wrist bone

Cartilage

Flexible connective tissue found in joints, fetal skeleton, and the lining of various parts of the body

Cartilaginous disk

Thick, circular mass of cartilage between the vertebrae of the spinal column

Cervical vertebrae

Seven vertebrae of the spinal column located in the neck

Clavicle

Curved bone of the shoulder that joins to the scapula; collarbone

Coccyx

Small bone consisting of four fused vertebrae at the end of the spinal column; tailbone

Compact bone

Hard bone with a tightly woven structure

Condyle

Rounded surface at the end of a bone

Crest

Bony ridge

Diaphysis

Long middle section of a long bone; shaft

Diarthroses

Freely movable joints

Disk

See cartilaginous disk

Dorsal vertebrae

Thoracic vertebrae

Elbow

Joint between the upper arm and the forearm

Endosteum

Lining of the medullary cavity

Epiphyseal plate

Cartilaginous tissue that is replaced during growth years but eventually calcifies and disappears when growth stops

Ethmoid bone

Irregular bone of the face attached to the sphenoid bone

Ethmoid sinuses

Sinuses on both sides of the nasal cavities between each eye and the sphenoid sinus

Fascia

Sheet of fibrous tissue that encloses muscles

Femur

Long bone of the thigh

Fibula

Smallest long bone of the lower leg

Fissure

Deep furrow or slit

Flat bones

Thin, flattened bones that cover certain areas, as of the skull

Fontanelle

Soft, membranous section on top of an infant’s skull

Foramen

Opening or perforation through a bone

Foramen magnum

Opening in the occipital bone through which the spinal cord passes

Fossa

Depression, as in a bone

Frontal bone

Large bone of the skull that forms the top of the head and forehead

Frontal sinuses

Sinuses above the eyes

Heel

Back, rounded portion of the foot

Humerus

Long bone of the arm connecting to the scapula on top and the radius and ulna at the bottom

Ilium

Wide portion of the hip bone

Insertion

Point at which a muscle attaches to a movable bone

Intervertebral disk

See cartilaginous disk

Involuntary muscle

Muscle not movable at will

Irregular bones

Any of a group of bones with a special shape to fit into certain areas of the skeleton, such as the skull

Ischium

One of three fused bones that form the pelvic girdle

Joint

Place of joining between two or more bones

Lacrimal bone

Thin, flat bone of the face

Lamina

Thin, flat part of either side of the arch of a vertebra

Ligament

Sheet of fibrous tissue connecting and supporting bones; attaches bone to bone

Long bone

Any bone of the extremities with a shaft

Lumbar vertebrae

Five vertebrae of the lower back

Malleolus

Rounded protrusion of the tibia or fibula on either side of the ankle

Mandible

U-shaped bone of the lower jaw

Mandibular bone

Mandible

Marrow

Connective tissue filling the medullary cavity, often rich in nutrients

Mastoid process

Protrusion of the temporal bone that sits behind the ear

Maxillary bone

Bone of the upper jaw

Maxillary sinus

Sinus on either side of the nasal cavity below the eyes

Medullary cavity

Soft center cavity in bone that often holds marrow

Metacarpal

One of five bones of the hand between the wrist and the fingers

Metaphysis

Section of a long bone between the epiphysis and diaphysis

Metatarsal bones

Bones of the foot between the instep (arch) and the toes

Muscle

Contractile tissue that plays a major role in body movement

Musculoskeletal system

System of the body including the muscles and skeleton

Nasal bones

Bones that form the bridge of the nose

Nasal cavity

Cavity on either side of the nasal septum

Neural canal

Space through which the spinal cord passes

Nucleus pulposus

Fibrous mass in the center portion of the intervertebral disk

Occipital bone

Bone that forms the lower back portion of the skull

Olecranon

Curved end of the ulna to which tendons of the arm muscles attach; bony prominence of the elbow

Origin

Point at which muscles attach to stationary bone

Osseous tissue

Connective tissue into which calcium salts are deposited

Ossification

Hardening into bone

Osteoblast

Cell that forms bone

Osteoclast

Large cell that reabsorbs and removes osseous tissue

Osteocyte

Bone cell

Palatine bone

Bone that helps form the hard palate and nasal cavity, located behind the maxillary bones

Parietal bone

Flat, curved bone on either side of the upper part of the skull

Patella

Large, sesamoid bone that forms the kneecap

Pelvic cavity

Cup-shaped cavity formed by the large bones of the pelvic girdle; contains female reproductive organs, sigmoid colon, bladder, and rectum

Pelvic girdle

Hip bones

Pelvis

Cup-shaped ring of bone and ligaments at the base of the trunk

Periosteum

Fibrous membrane covering the surface of bone

Phalanges

Long bones of the fingers and toes

Phosphorus

Mineral important to the formation of bone

Process

Bony outgrowth or projection

Pubes

Anteroinferior portion of the hip bone

Pubic symphysis

Joint between the two pubic bones

Radius

Shorter bone of the forearm

Rib

One of twenty-four bones that form the chest wall

Sacrum

Next-to-last spinal vertebra made up of five fused bones; forms part of the pelvis

Scapula

Large flat bone that forms the shoulder blade