Ch. 3 Flashcards
4 Groups of Tissues
Epithelial, connective, muscle, neural
3 ways to visualize cells
Light microscopy*, transmission electron microscopy, and scanning electron microscopy
How many nuclei does each epithelial tissue have?
one
What are epithelial tissues attached to?
basement membrane
How do cells form tissues?
Cell-cell junctions and cell-matrix junctions
tight junction
keeps cells together to prevent things from sneaking between the cells
Gap junction
for communication purposes (heart), allows certain types to come in, others not
A group of specialized cells that perform a limited set of functions
Tissues
Characteristics of epithelial tissue
cellularity, polarity (apical versus basolateral), attachment to basal lamina, avascularity (without blood flow), arranged in sheets or layers
Functions of epithelial tissue
physical protection, controls permeability, provide sensation, produces secretions
Cilia
beat in a coordinated fashion and move substance along the surface of the epithelial cell
Where are cilia found?
in the respiratory system
microvilli
foldings on the apical surface, increase surface area of cell, found a lot in cells specialized for absorption and secretion
Name 3 types of layered epithelial tissue
Simple, stratified, and pseudostratified
Simple Layer is…
every cell attached to basement membrane, one layer
Stratified Layer is…
second layer or more, not every cell is attached to basement membrane
Pseudostratified layer is…
looks stratified, but every cell is attached to basement membrane (upper respiratory system)
Squamous cell shape…
flat
Name 3 types of epithelial cell shapes
squamous, cuboidal, or columnar
You name epithelial tissue by describing the…
layers (simple or stratified) and shape (simple squamous or simple columnar)
Simple Squamous (locations)
mesothelia (ventral body cavities), endothelia (lining heart, blood vessels, and lymphatic vessels), lungs, kidneys (glomerular capillary)
Stratified Squamous (keratinized) (location)
epidermis of skin
Stratified squamous (non-keratinized) (location)
lining of mouth, throat, esophagus, rectum, anus, vagina
Simple cuboidal (location)
ducts of glands, kidney tubules
Stratified cuboidal (location)
ducts of some glands (sweat glands)
simple columnar (location)
nonciliated: stomach, intestines
ciliated: fallopian tubes, uterus
stratified columnar (location)
pharynx, anus, urethra
pseudostratified ciliated columnar (location)
upper respiratory system (nasal cavity, trachea, bronchi)
transitional (location)
urinary bladder, ureters, urethra
Special cases of epithelial tissue…
transitional and pseudostratified columnar
(function) present at sites where the processes of filtration (such as blood filtration in the kidneys), diffusion (such as diffusion of oxygen into blood vessels of the lungs), and secretion (in serous membrane) occur. Not found in body areas that are subject to mechanical stress (wear and tear)
Simple squamous epithelium tissue
Simple cuboidal epithelium tissue (function)
secretion and absorption
(function) secretion and absorption, but the larger columnar cells contain more organelles and are therefore capable of a higher level of secretion and absorption than are cuboidal cell. Secreted mucus serves as a lubricant for the linings of the digestive, respiratory, and reproductive tracts, and most of the urinary tract. Mucus also helps prevent destruction of the stomach lining by acidic gastric juice secreted by the stomach
Nonciliated simple columnar epithelium tissue
(function) the cilia beat in unison, moving the mucus and any foreign particles toward the throat, where they can be coughed up and swallowed or spit out. Coughing and sneezing speed up the movement of cilia and mucus. Cilia also help move oocytes expelled from the ovaries through the uterine (fallopian) tubes into the uterus
Ciliated Simple Columnar epithelium tissue
nonciliated pseudostratified columnar epithelium tissue (function)
absorption and secretion
ciliated pseudostratified columnar epithelium tissue (function)
secretes mucus that traps foreign particles, and the cilia sweep away the mucus for eventual elimination from the body
stratified squamous epithelium tissue (function)
protection against abrasion, water loss, UV radiation, and foreign invasion. Both types of stratified squamous epithelium form the first line of defense against microbes
stratified cuboidal epithelium tissue (function)
protection and limited secretion and absorption
stratified columnar epithelium tissue (function)
protection and secretion
transitional epithelium (urothelium) (function)
it allows the urinary organs to stretch to hold a variable amount of fluid without rupturing, while still serving as a protective lining
endocrine glands epithelium tissue (function)
hormones regulate many metabolic and physiological activities to maintain homeostasis
endocrine glands (location)
pituitary glands at base of brain, pineal gland in brain, thyroid and parathyroid glands near larynx, adrenal glads superior to kidneys, pancreas near stomach, ovaries in pelvic cavity, testes in scrotum, and thymus in thoracic cavity
exocrine glands (function)
produce substances such as sweat (to help lower body temp), oil, earwax, saliva, or digestive enzymes
exocrine glands (location)
sweat, oil, and earwax glands of the skin; digestive glands such as salivary glands, which secrete into mouth cavity, and pancreas, which secretes into the small intestine
