Epithelial Tissue Flashcards
(19 cards)
What are the 4 main types of tissues
Epithelial
Connective
Muscle
Nervous
The cells of epithelial tissues are held together by an acellular glue called a ________
Basement membrane
What is the main difference between epithelial and connective tissue
Epithelial = many cells, densely packed with little extra cellular matrix between
Connective = less dense, small number of nuclei, lots of ECM
List the characteristics of epithelium
Protective covering of surfaces inside and outside the body
Has free, basal and lateral surfaces
Avascular
Capable of regeneration
What are the functions of epithelial tissue
Protect underlying structure
Act as barrier
Permit the passage of substances. (Diffusion/filtration)
Secretion
Absorption
What are the two specialized cell surface modifications
Microvilli (brush border) - stationary, increase SA for secretion and absorption i.e., in digestive system
Cilia - can move materials across a cell surface i.e., trachea can move materials out of lungs
What does simple epithelial functionally allow
Diffusion of gases, filtration of blood, secretion and absorption
What does stratified epithelial functional allow
Protection from abrasion
What does pseudostratified epithelial functionally allow
Modification of simple epithelial and allow for secretion and movement of mucus
What does squamous epithelial functionally allow
Diffusion or act as a filter
What does cuboidal or columnar epithelial functionally allow
Secretion or absorption , may include goblet cells that produce and secrete mucus
Describe the structure, some locations where this is found and function of this tissue
Simple squamous
Lining of blood vessels, alveoli of lungs, bowman’s capsule of kidney, lining of serous membrane
Diffusion, filtration, secretion
Describe the structure, some locations where this is found and function of this tissue
Simple columnar
Can have microvilli or cilia
Helps with movement, secretion and absorption
Located in glands, bronchioles, uterus, uterine tubes, stomach, intestine, gallbladder, ventricles of brain
Describe the structure, some locations where this is found and function of this tissue
Pseudo stratified columnar
Associated with goblet cells to secrete mucus
Lining of upper respiratory tract and non ciliates in urethra and epididymis
Synthesize and secrete mucus, move mucus and absorption and protection
Describe the structure, some locations where this is found and function of this tissue
Simple cuboidal epithelium
Kidney tubules, glands and their ducts, surface of ovaries
Secretion and absorption
Describe the structure, some locations where this is found and function of this tissue
Stratified squamous epithelium
Non keratinized in mouth, throat, esophagus, anus, valine
Keratinized in the skin
Protects against abrasion, u,Travis let radiation, water loss and infection
Describe transitional epithelium
Stratified where cells change shape depending on the amount of distension or stretch of the organ
I.e., lining of the urinary tract
Starts as cuboidal and stretched to look squamous
Accommodates fluctuations in the volume of fluid in an organ or tube and protect against the caustic or acidic effects of urine
Describe endocrine glands
Have no open contact with exterior, no ducts and produce hormones
I.e., thyroid gland , hormone gets released from follicle and taken up or secreted into the bloodstream to get into systemic circulation
Exocrine gland
Have open contact with exterior and have ducts
Sweat glands, oil gland, mammary glands, digestive system
Cells around produce sweat and enter lumen, make its way to the duct to the obtuse surface of the body
I.e., skim
