Skin - The integumentary system Flashcards
epidermis
the outermost layer of skin, provides a waterproof barrier and creates our skin tone.
dermis
beneath the epidermis, contains tough connective tissue, hair follicles, and sweat glands.
deeper subcutaneous tissue
(hypodermis) is made of fat and connective tissue
melanocytes
pigment melanin. Melanocytes are located in the epidermis.
Composition of epidermis
keratinized, stratified squamous epithelium. It is made of four or five layers of epithelial cells, depending on its location in the body. It does not have any blood vessels within it
thin skin
Skin that has four layers of cells
Thick skin
found only on the palms of the hands and the soles of the feet. It has a fifth layer, called the stratum lucidum, located between the stratum corneum and the stratum granulosum
keratinocyte
is a cell that manufactures and stores the protein keratin.
Keratin
is an intracellular fibrous protein that gives hair, nails, and skin their hardness and water-resistant properties.
slough away
being replaced by cells from the deeper layers
basal layer
consists of cuboidal cells
stratum basale
is the deepest epidermal layer and attaches the epidermis to the basal lamina, below which lie the layers of the dermis.
dermal papilla
finger-like projection, or fold,found in the superficial portion of the dermis. Dermal papillae increase the strength of the connection between the epidermis and dermis; the greater the foldin
stratum basale
is a single layer of cells primarily made of basal cells
basal cel
cuboidal-shaped stem cell that is a precursor of the keratinocytes of the epidermis.
Merkel cell
which functions as a receptor and is responsible for stimulating sensory nerves that the brain perceives as touch. These cells are especially abundant on the surfaces of the hands and feet.
stratum spinosum
spiny in appearance due to the protruding cell processes that join the cells via a structure called adesmosome
desmosome
desmosomes interlock with each other and strengthen the bond between the cells.
Langerhans cell,
which functions as a macrophage by engulfing bacteria, foreign particles, and damaged cells that occur in this layer
what is pus
deadleukocytesfrom the body’simmune response(mostlyneutrophils) and white blood cells
Function of skin
barrier.
protection.
immunological.
secretion.
thermoregulation.
sensitivity.
absorption.
types of fibres
Collagen
Elastin
Reticular
Reticular
Reticular fibres to help disperse mechanical forces, which may be applied to the skin.
Elastin
Elastin to allow the skin to stretch (though this can break when overstretched, for example, in pregnancy. This results in silvery lines known as stretch marks);
Collagen
Collagen to provide strength
Fibroblasts and tissue macrophages
are essential for wound healing
tissue mast cells
produce histamine and heparin in response to foreign substances
neutrophils and lymphocyte
Neutrophils provide the first line of defense of the innate immune system by phagocytosing, killing, and digesting bacteria and fungi. … The movement of compensating ions produces conditions in the vacuole conducive to microbial killing and digestion by enzymes released into the vacuole from the cytoplasmic granules.
lymphocyte is one type of white blood cell in the vertebrate immune system. Lymphocytes include natural killer cells, T cells, and B cells.
Functions ofthe integumentary system
Covering. Deepertissues, protecting from dehydration injury and germ invasion.
Regulates.Body temperature.
Manufactures. Vitamin D.
Site. Nerve Endings (1 square inch contains 72 ft of nerves and 100s of receptors)
Storage. Fats, Glucose, Water, and Salts.
Screening. …
Absorbs.
