Epithelial Tissues Flashcards
what are tissues
a group of cells working together to perform a function
what is the study of tissues
histology
what are the four (4) main types of tissues that make up body organs
epithelial, connective, muscle and nervous
what are some functions of epithelial tissues
protection - covers surfaces and lines cavities
absorption and secretion
permeability - determine what goes in/out
what are the characteristics of epithelial tissue
tightly packed cells - very little intercellular space
avascular
contains a free surface
regenerates quickly
contains a basement membrane that connects it to the connective tissue underneath
contains nerves
what are the functions of the basement membrane
provides adherence
permeability
surface for mitosis
how are epithelial tissues named and classified
by shape (squamous, cuboidal, columnar) and layer (simple or stratified) and takes the name of the shape by the cell at the apical (free) surface
what type of tissue would have ONE layer of FLAT cells
simple squamous tissue
where is simple squamous tissue found
lining blood vessels, body cavities, and air sacs
also found in kidney tubules
why are simple squamous epithelium found in blood vessels and around body cavities
they provide a thin layer or cells for diffusion across the cells
what is endothelium
simple squamous epithelium that lines the blood vessels
what is mesothelium
simple squamous epithelium lining the abdominal and thoracic cavity
what type of tissue would have ONE layer of CUBOIDAL cells
simple cuboidal tissue
where would you find simple cuboidal tissue
in ducts, glands, kidney tubules and the thyroid gland
what are functions of cuboidal cells
secretion and absorption
what type of tissue would have ONE layer of tall cells
simple columnar tissue
where would you find simple columnar cells
lining of the gastrointestinal tract, fallopian tubes, and larger ducts
what are some functions of columnar cells
secretion, absorption, and some may be goblet cells to produce mucous
what are goblet cells
cells that produce mucous to aid in trapping debris and unwanted material or to better absorb substances
Y/N
do some columnar cells have additional structures on the free surface such as microvilli or cilia
Yes
where would a columnar cell be found with microvilli on the apical (free) surface
the digestive tract for better absorption
what type of cell would have SEVERAL layers of cells and have FLAT cells at the apical (free) surface
stratified squamous epithelial tissue
what is keratinized stratified squamous tissue
dead cells containing the protein keratin to aid in protecting against abrasion
where can you find stratified squamous tissue
in the skin, lining of the mouth, esophagus, vagina and rectum
any area where protection is needed
where can you find stratified cuboidal/columnar tissue
in sweat glands and ducts. stratified columnar is mainly found in salivary gland ducts
what type of tissue contains cells that can change their shape to stretch and recoil
transitional epithelial tissue
where can you find transitional epithelial tissue
the bladder
T/F
the organ with transitional epithelial tissue WILL expand when stretched
True
what type of tissue appears to have more than one layer but actually every cell touches the basement membrane
pseudostratified tissue
where can you find pseudostratified epithelial tissue
in the lining of the respiratory tract and part of the male reproductive system
pseudostratified epithelium is often ciliated. this tissue typically has goblet cells to produce _______
mucin - this is mucous
what type of tissue makes up glands and ducts
epithelial tissue
what are the differences between endocrine and exocrine glands
exocrine glands secrete substance into ducts and glands by exocytosis while endocrine glands secrete straight into the blood stream
holocrine glands are a type of exocrine gland. what is the product of holocrine glands and how does it secrete its product
holocrine glands secrete oil in the face
the oil and other substances will build up in the cell and when full, the whole cell will break off
holocrine - whole - whole cell breaks off
merocrine glands are a type of exocrine gland. what is the product of merocrine glands and how does it secrete its product
merocrine glands secrete sweat
the sweat will build up in the cell and leave through exocytosis
apocrine glands are a type of exocrine gland. what is the product of apocrine glands and how do they secrete their product
apocrine glands secrete mammary milk
they secrete milk by the build up of the fluid at the apical side of the cell and when full that portion of the cell will break off
T/F
exocrine and endocrine glands ARE NOT made of epithelial tissue
False
