Chapter 4 - Skin and Body Membranes Flashcards
Mucous membrane
A type of membrane that lines all body cavities that open up to the exterior
Cutaneous membrane
The skin of the body, a dry membrane that is exposed to air
Serous membrane
A type of membrane that lines all body cavities that are closed to the exterior (except for the dorsal body cavity and joint cavities) and secretes serum
Serosa
Another name for the serous membrane
Mucosa
Another name for the mucous membrane
Parietal layer
A serous layer that lines a specific portion of the wall of the ventral body cavity, and it folds in on itself to form the visceral layer
Visceral layer
A serous layer that covers the outside of the organs in that cavity
Serous fluid
A thin clear fluid secreted by the parietal and visceral layers that separate the serous layers
Peritoneum
The serosa that lines the abdominal cavity and covers its organs
Pleura
Serosa that surrounds the lungs
Pericardium
Serosa that surrounds the heart
Synovial membrane
Membrane composed of soft areolar connective tissue with no epithelium that lines the fibrous capsules surrounding the joints
Bursae
Small sacs made up of connective tissue located at friction points, especially joints
Keratin
A tough, insoluble protein found in tissues such as hair, nails, and epidermis of the skin
Cornified
A process when the skin hardens and becomes horn shaped
Epidermis
The outer layer of the skin made up of stratified squamous epithelium that is capable of keratinizing, or becoming hard and tough
Dermis
The skin layer underneath the epidermis made up of mostly dense connective tissue, it is firmly connected with the epidermis and is fairly tear resistant
Subcutaneous tissue
The layer deep to the dermis that is made up of adipose tissue. It is not considered to be part of the skin, but it does connect the skin to underlying organs and provides a site for nutrient (fat) storage.
Hypodermis
Another name for the subcutaneous tissue
Arrector pill muscle
Tiny, smooth muscles attached to to hair follicles; when activated, they cause the hair to stand upright
Strata
Many layers, plural for stratum
Stratum basale
The deepest cell layer of the epidermis containing the most adequately nourished epidermal cells. It is also called the stratum germinativum since the cells are constantly dividing
Stratum spinosum
The fourth layer of the epidermis that contains cells with thick bundles of intermediate filaments made of pre-keratin
Stratum granulosom
The third layer of the epidermis covered with flattened cells filled with deteriorated organelles and cytoplasms full of keratohyalin granules
Stratum lucidum
A layer of the epidermis that is only present in skin surfaces that is hairless and extra thick (on the palms of hands or soles of the feet). It is composed of three to five layers of dead, flattened keratinocytes
Stratum corneum
The outermost layer of the epidermis, usually 20-30 cell layers thick but accounts for three-quarters of the epidermal thickness. It is completely filled with cornified (keratinized) cells
Keratinocytes
The most common cells in the epidermis found in the stratum basal that produce keratin
Dandruff
Small pieces of dead skin in a person’s hair
Melanin
A pigment that determines skin color, the more it produces, the darker the skin color