histology note cards Flashcards
what is the epithelial tissue?
The lining tissue that forms the boundary between our boy and the external environment.
What are the functions of the Epithelial tissue?
Protection, Absorption, Filtration and Secretion.
What is the top of the Epithelial tissues structure called?
The top tissue is called the free surface or apical surface.
What is the bottom surface called?
The basal surface.
What is the membrane underneath the Basal surface called?
The Basement membrane.
What do all of these tissues have in common?
They are all avascular. (no blood vessels.)
What is the difference between simple and stratified epithelial tissues?
Simple epithelial tissue: has only one layer of cells
Stratified tissue: more than one layer of cells.
What is a simple squamous epithelium tissue?
A sling, flat layer of cells that is thin and permeable.
What is a simple squamous epithelium tissues function? And where can it be found?
Rapid diffusion of materials and can be found in blood vessels & lung tissues.
What is a simple cuboidal epithelium?
A sling layer of cube-shaped cells.
What is a simple cuboidal epithelium tissues function? And where can it be found?
It’s function is secretion & absorption of substances. And can be found in the tissues of the kidney.
What is the definition of a simple columnar epithelium?
A single layer of tall, closely packed cells. (May have cilia and goblet cells, which secrete mucus.)
What is the function of a Simple columnar epithelium tissues and where can it be found?
It’s function is the secretion of mucus for protection & absorption of substances. It can be found the in the lining of the digestive tract.
Summary of the Epithelial tissue.
Epithelial tissue is the lining that protects the body form the external environment. All epithelial tissues have a free surface, a basal surface, and a basement membrane. Simple epithelial tissues are made of one layer of cells that can vary in shape.
What is a Stratified squamous epithelium tissues? And where can it be found?
These thick layers provide protection for the underlying layers. And it can be found in the epidermal layer of the skin.
Describe what a Stratified cuboidal epithelium tissue is and where it can be found?
It has more than one layer of cuboidal cells. It is rare in the body, and can be found in salivary & mammary glands.
Describe what a stratified columnar epithelium tissues is and where can it be found?
It’s free surface is lined with columnar cells. It is rare in the body and is found in your larynx and the male urethra.
What is a pseudostratified epithelium?
In pseudo-stratified epithelium, cell nuclei are found at different levels, so it appears stratified, though it is not.
What is pseudostratified epithelium tissues function and where can it be found?
Its function is secretion & absorption. And it is found in most of the upper respiratory tract.
What Is transitional epithelium? And where can it be found?
The free surface cells of transitional epithelium vary in appearance based on the stretching of the tissue. It can be found in the lining of the urinary bladder.
“Transition” = change shape with elasticity. (function)
Summary of Stratified epithelial tissues:
Stratified epithelial tissues have more than one layer and can vary in cell shape. Pseudo-stratified epithelium appears to have multiple layers and transitional epithelium can change its appearance as it stretches.
What is glandular epithelium?
A gland made of a group of cells that secrete a fluid substance.
The glands are classified in two ways: complexity & how substances are secreted (exocrine & endocrine)
How do exocrine and endocrine glands differ?
Exocrine glands: Secrete substances outward through a duct. ex: sweat glands
Endocrine glands: Ductless glands that secrete hormones through the bloodstream. ex: thyroid gland.
What are the types of exocrine glands?
Merocrine glands, Apocrine glands, and Holocrine glands.
What does a Merocrine gland do?
Cells excrete the products (substances) via exocytosis. An example is; sweat glands.
Mero= “part”
What is a Apocrine gland and what does it do?
A portion of the cell pinches off with the secreted products. An example is mammary glands.
Apo= “tip”
What is a Holocrine gland and what does it do?
Cells rupture and spill products into the duct. An example would be Sebaceous (oil) glands in the skin.
“Hol” = whole
What are the characteristics of endocrine glands?
-Endocrine glands Secrete hormones into the blood so they can be delivered over longer distances.
-The cells are packed tightly together with capillaries running through the glandular tissue.
-Cells excrete products through exocytosis into the blood
Examples: thyroid, thymus, adrenal glands, and pancreas.
Summary of Glandular tissues:
Glandular tissue is a specialized type of Epithelial tissue. Endocrine glands secrete hormones into the blood, while exocrine glands use tube-like ducts to secrete their products. Exocrine glands differ in the portion of the cell that is secreted with the product.
epithe
upon
hist-
tissue
-ology
study of
endo-
‘within, inner, absorbing or containing.”
exo-
“outside’ or external
adipo-
fat, fatty
chondro-
cartilage, grain, granular
-cyte
cell
erythro-
red, reddish
osteo-
bone
leuk-
white
