Lab 2 Review: Integumentary System Flashcards
Polarity (re epithelia)
That epithelia have an apical surface, exposed to the body exterior (keritanized or not, ciliated or not), and basal surface, attached to a noncellular basal lamina made of glycoproteins and fine collagen fibers
specialized contacts/cellularity (epithelia)
cells fit close together to form a continuous sheet; attached by lateral contacts like tight junctions/desmosomes/gap junctions
supported by connective tissue (epithelia)
epithelia rest on a basement membrane composed of mostly collagen fibers: reinforces epithelial sheet, helps to resist stretching and tearing
function of simple squamous epithelia
easy diffusion and filtration of substances, secretion of lubricating substances in serosae
location of simple squamous epithelia
kidney glomeruli, air sacs of lungs, lining of heart, blood vessels, and lymphatic vessels, lining of ventral body cavity (serosae)
function of stratified squamous epithelia
protects underlying tissues in areas subject to abrasion
location of stratified squamous epithelia
nonkeratinized: moist linings of the esophagus, mouth and vagina
keratinized: epidermis of skin
function of simple cuboidal epithelia
secretion and absorption
location of simple cuboidal epithelia
kidney tubules, ovary surface, ducts and secretory surfaces of small glands
function of simple columnar epithelia
absorption; secretion of mucus, enzymes and other substances; ciliated propels mucus or reproductive cells
location of simple columnar epithelia
nonconciliated: most of digestive tract, gall bladder, excretory ducts of some glands
ciliated: small bronchi, uterine tubes, some regions of uterus
two major body cavities
dorsal and ventral
serosa
a thin, double-layered epithelial membrane (simple squamous) that secretes and is filled with serous fluid
-lines the pleural cavities, pericardial cavity, and peritoneal cavity
-outer layer: parietal; inner layer: visceral
outer layer of the serosa (lines internal body wall)
parietal
inner layer of the serosa (covers the internal organs)
visceral
three types of protection that the skin provides
chemical (low pH from sweat and sebum against bacteria; melanin against UV), physical (keratin and glycolipids against water entry and loss), and biological (immune system against pathogens)
how does the integumentary system thermoregulate
dilation and constriction of blood vessels in skin; sweat
types of cutaneous sensation and their corresponding sense receptors
-temp (thermoreceptors)
-touch (tactile/meissner’s corpuscles (dermis), merkel/tactile cells (epidermis) and hair follicle receptors)
-pressure (lamellar/pascinian corpuscle)
-pain (free nerve endings)
metabolic functions of the integument
-synthesis of vit D precursor
-activate steroid hormones
-chemical conversion of carcinogens
blood reservoir of integument
-holds 5% of blood in body
-shunts it to places that need it (metabolically active tissue like wounds)
excretion of integument
excretion of salt and nitrogenous waste (sweat)
two types of tissue repair
regeneration and fibrosis
tissue regeneration
Repair of tissue injury by replacement of damaged or destroyed tissue with the same kind of tissue
Fibrosis
Repair of tissue injury by replacement of damaged or destroyed tissue with scar tissue
*Fibrous connective tissue
burns
-heat denatures proteins and causes cell death
-too much loss of fluid, containing proteins and electrolytes, can lead to renal shutdown and circulatory shock
-risk of infection
first line therapy for severe burns
*IV fluid replacement
*Nutrient supplementation
what’s a secondary risk of severe burns after shock, loss of fluids, etc.?
risk of infection
epithelium: vascular or avascular?
avascular. vasculature is in the connective tissue, not in the epithelial cells
function of pseudo-stratified columnar epithelium
secretion and (ciliated) propulsion of mucus
location of pseudostratified columnar epithelium
non-ciliated: vas deferens and male urethra
ciliated: upper respiratory tract and trachea
function of stratified cuboidal epithelia
(rare): secretion
location of stratified cuboidal epithelia
Lines ducts of large glands
(i.e. sweat glands and
mammary glands)
function of transitional epithelia
stretch
location of transitional epithelia
Lines bladder, ureter
and part of the
urethra
functions of the integument:
please buy me expensive cornell books
protection, body temp regulation, metabolic function, excretion, cutaneous sensation, blood reservoir
layers of the epidermous
come lets get sun burned
corneum; lucidum; granulosum; spinosum; basale
stratum corneum
*Most superficial layer
*Thick layer (20 – 30
rows) of dead cells
represented by flat
membranous sacs filled
with keratin
*Accounts for up to 3/4
of the epidermis
*Glycoproteins between
cells enable a water-
resistant layer
stratum lucidum
*Thin layer (2 – 3 rows) of clear, flat,
dead keratinocytes
*Appears as a thin translucent band just
above the stratum granulosum
*Only present in thick skin
Stratum Granulosum
*Thin layer (3 – 5 rows) of flattened cells
*Cells are undergoing keratinization in this
layer
-Causes cells to flatten and nuclei and organelles to
disintegrate
Stratum Spinosum
*Several layers of keratinocytes
*Melanin granules and epidermal dendritic
cells are most abundant in this layer
Stratum Basale
*Deepest epidermal layer
*Connected to the dermis
*Consists of a single row of
mostly mitotic stem cells that
give rise to keratinocytes
*10 – 25% of cells are
melanocytes
*Some tactile (Merkel) and
epidermal dendritic
(Langerhans) cells also found
here
