Anatomy and Physiology Exam #2

achondroplasia

a genetic condition affecting a protein in the body called the fibroblast growth factor receptor - “dwarfism”

appendicular skeleton

bones of the limbs and limb girdles that are attached to the axial skeleton

appositional growth

growth in width

apocrine glands

glands that lose small portions of their glandular cell bodies during secretion

arrector pili muscle

the small, involuntary muscle in the base of the hair follicle

axial skeleton

portion of the skeletal system that consist of the skull, rib cage and vertebral column

basal cell carcinoma

most common and least severe type of skin cancer - often characterized by light or pearly nodules

bone canaliculi

microscopic canals between the lacunae of ossified bone

central canal

a tiny channel found within the spinal cord - lies below and is connected to the ventricular system of the brain

ceruminous glands

modified sweat glands, located in external ear canal, secretes cerumen (earwax)

compact bone

hard, dense bone tissue that is beneath the outer membrane of a bone

cutaneous plexus

network of blood vessels between reticular layer and hypodermis

dermis

inner layer of skin

diaphysis

shaft of a long bone

eccrine glands

glands that produce sweat - found over most of the body

endochondral ossification

process of transforming cartilage into bone

endosteum

membranous lining of the hollow cavity of the bone

epidermal ridges

downward waves of epidermis - fingerprints

epidermis

outermost layer of skin

epiphysis

end of a long bone

fracture

to break (a bone)

gigantism

a condition produced by hypersecretion of growth hormone during the early years of life

hair follicle

sac within which each hair grows

hard (bony) callus

bony collar around spongy bone replacing the fibrocartilage callus - third step in healing of a fracture

hemotoma

a solid swelling of clotted blood within tissues

hypodermis

the layer of skin beneath the dermis, which serves as fat storage

intervertebral discs

separate and cushion the vertebrae

intramembranous ossification

bone develops from a fibrous membrane

keratin

hard protein material found in the epidermis, hair and nails

keratinocytes

the most abundant epidermal cells, they function mainly to produce keratin

kyphosis

excessive outward curvature of the spine, causing hunching of the back

lucanae

small cavities in bone that contain osteocytes

lamallae

rings around the central canal, sites of lucanae

longitudinal growth

increases a bone’s length

lordosis

abnormal anterior curvature of the lumbar spine (sway-back condition)

mammary glands

specialized organs in mammals that produce milk

medullary cavity

cavity within the shaft of the long bones filled with bone marrow

melanin

a pigment that gives skin its color

melanocytes

cells that produce melanin

melanoma

the most serious form of skin cancer - melanocytes start to grow out of control

model

a three-dimensional representation of human or animal anatomy

nail

outgrowth of the skin, composed of keratin at the end of each finger and toe

osteoblasts

bone building cells

osteoclasts

bone destroying cells

osteocyte

maintains bone

osteogenic cells

stem cells

osteon

a structural unit of compact bone

osteoporosis

a condition in which the body’s bones become weak and break easily

papillary layer

outer layer of the dermis, directly beneath the epidermis - loose connective tissue

periosteum

a dense fibrous membrane covering the surface of bones

primary ossification center

region, deep in the periosteal collar, where bone development starts during endochondral ossification

red marrow

produces blood cells

reticular layer

deeper layer of the dermis that supplies the skin with oxygen and nutrients - dense connective tissue

rule of 9’s

head and neck - 9%

upper extremities - 9% each

lower extremities - 9% each

front trunk - 18%

back trunk - 18%

scoliosis

abnormal lateral curvature of the spine

sebaceous follicles

discharge directly onto skin surfaces

sebaceous glands

secrete oil into the hair follicles where the hair shafts pass through the dermis

sebum

oily substance secreted by sebaceous glands

soft callus

mixture of hyaline cartilage and collagenous connective tissue

spongy bone

layer of bon tissue having many small spaces and found just inside of compact bone

squamous cell carcinoma

malignant tumor of squamous epithelium cells in the epidermis

subpapillary plexus

network of small arteries in papillary layer

capillaries drain into small veins that lead to larger veins in subcutaneous layer

sweat glands

produce sweat

trabeculae

supporting bundles of bony fibers in cancellous (spongy) bone

vertebrae

backbones - spine

yellow marrow

soft, fatty material found in the medullary cavity of long bones