Unit 1 Flashcards
What are the 4 basic types of tissue
Epithelial
Connective
Nervous
Muscle
What are the general functions of epithelium
Absorption
Secretion
Protectoin
What are the basic characteristics of epithelium
1) Cells are adjacent to each other
2 )Assiciated with a complete or partial basement membrane
3) Avascular
4) Associated with vascular connective tissue
What are the functions of the basement membrane
Surface for attachemtn
Molecular filter
Limits stretching
directs migration of cell
How to epithelial cells get nutrition
Diffusion
Why is epithelial tissue associated with Vascular connective tissue
To get nutrition
for a source of defensive cells
What holds cells together
Cell junctions
What are the types of cell junctions
Zonula Occludens
Zonula Adherens
Macula Adherens
Gap Junctions
What are Zonula Occludens
Junction that allows for intrinsic membrane proteins between cells
What are the functions of Zonula Occludens
Provide strong attachment
Prevents passage of material between cells
What is the function of Zonula Adherens
Strong attachment
Provide cell structural stability
What are the regions of a zonula Adherens
Cadherins (linkage) Marginal bands (attach cytoskeleton to cell membrane)
What is the function of Macula Adherens
Provide strong attachment
What is the function of a gap junction
Strong attachment
Transport materials between cells
What makes up a gap junction
6 connexins (proteins) arranged in a cylinder
What is the order of structures that make up a Junctional complex
Zonula Occludens
Zonula Adherens
Macula Adherens
What do Hemidesmosomes do
Connect epithelial cells to the basal lamina
What are focal point contacts
Integrin binds to a structural Connective tissue glycoproteins and also connects to cytoskeleton
What is Bullous Pemphgoid
Autoimmune skin disease causing blistering lesions
What causes Bullous pemphgoid
Antibodies bind to proteins in hemidesmosomes
What is Pemphigus Vulgaris
An autoimmune disease causeing blisters that do NOT heal, can be fatal (bleeding)
What causes Pemphigus vulgaris
Antibodies bind to some parts of desmosomes
What is Cholera
Bacterial infection of small intestines
What causes Cholera
Toxins disrupt zonula occludens, allows for water + electrolytes loss from connective tissue below epithelium
What are the types of epithelium
Simple epithelium
Stratified Epithelium
What are the types of Simple Epithelium
Simple Squamous
Simple Cuboidal
Simple Columnar
Ciliate pseudostratified columnar epithelium
Where are Simple Squamous cells found
Lungs
Kidney
Serosa
What is the function of Simple Squamous
Absorption/diffusion
Where can you find Simple cuboidal cells
Exocrine ducts
Kidney tubules
What are the different cell types of Ciliated Pseudostratified columnar epithelium
Goblet cells
Ciliated Columnar cells
Basal cells
What is the function of Goblet cells
Produce mucus
What type of cell has varying heights and have the appearance of stratified epithelium
Ciliated Pseudostratified epithelium
What is the function of Ciliated columnar cells
Move mucus over cells
What is the function of basal cells
The be the stem cell for the epithelium
What are the different surface specializations of epithelium
Microvilli
Sterocilia
Cilia
Glycocalyx
What is the function of microvili
Increase SA + Absorption
What is the function of Sterocilia
Increase SA
What is the function of Cilia
Move something over a surface
What is the difference between Sterocilia and Cilia
Sterocilia are rigid with an actin core and cant move
What block the free surface of epithelium from absoption or secreting
Basal bodies
What is the layer of glycoproteins and carbohydrates that cover some epithelium
GLycocalyx
What is the function of the glycocalyx
Protection
Cell recognition
What are the types of Stratified Epithelium
Stratified Squamous Keratinized Stratified Squamous Stratified Cuboidal Stratified Columnar Transitional
What is the function of Stratified Squamous
Protection from Friction
What is the problem with Stratified squamous epithelium
No protection from drying
limited thickness due to distance from capillaries
What are the layers of Keratinized stratified epithelium
Stratum Basale Stratum Spinosum Stratum Ganulosum Stratum Lucidum Stratum Corneum
What layer of Keratinized Stratified epithelium has keratinocytes
Stratum Basal
Stratum Spinosum
Stratum Granulosum
What layer of Keratinized stratified epithelium is only on thick skin
Stratum Lucidum
Which layer of Keratinized Stratified Epithelium prevents Water loss, provides a barrier
Stratum Corneum
How long does the average Keratinized stratified epithelium live
28 days
What cell protects us from UV radiation
Melanocytes
What is the darker from of melanin called
Eumelanin
What is the lighter form of Melanin called
Pheomelanin
What destroys melanin
Lysosomes
What is skin colour influenced by
Environment
Genetics
Number of blood vessels
What cell recognize and process foreign antigens in the stratum spinosum
Langerhans cells
What cell provide touch receptors
Merkel cells
Where are merkel cell found
Stratum Basal
What cells increase due to UV exposure and what cells decrease due to UV exposure
Increase with UV= Melancytes
Decrease with UV = Langerhans cells
Where are Stratified Cuboidal cells found
Larger ducts in sweat glands, salivary galnds
What are the functions of Stratified cuboidal
Increase Protection
Provide barrier
Where are Stratified Columnar cells found
Large ducts in pancreas, urethra, conjunctiva of eye
What are the functions of Stratified columnar
Increase protection
Provide transition between epithelial types
Provide a barrier
Where would you find Transitional epithelium
The urinary tract
What are the functions of Transitional epithelium
Protection
Stretch
Barrier
Transitional epithelium have well developed ______
Zonula Occludens (tight junction)
What unusual feature do the superficial cells of Transitional epithelium have
Some are bi-nucleated
What is psoriasis vulgaris
Patch skin lesions
What causes Psoriasis Vulgaris
Accelerated Keratinocyte life cycle
Were do cells accumulate in Psoriasis Vulgaris
Stratium Corneum
Where is inflammation of Psoriasis vulgaris
Inflammation in dermal papillae
What are freckles
Spots of extra pigment due to increased melanin but not melanocyts
What is Vitiligo
Patches with lack of melanocytes
What causes moles
Proliferation of melancytes
What is caused when melanocytes fail to produce melanin
Albinism
What is the most common form of albinism
Tyrosinase is missing from melanocytes (cant convert tyrosine to melanin
What is the method of secretion by which the product is released into a duct or directly onto an epithelial surface
Exocrine secretion
What is a parenchyma
Components that are directly involved with the primary function (ex bicep and muscle cell)
What is a stroma
Components providing mechanical/metabolic support ie, nerves, blood vessels, lymph
What are the morphological ways to class and exocrin gland
Secretory units: Tubular vs Acinar
Duct Arrangments: Unbranched vs branched
What is the most common method of exocrine gland secretion
Merocrine = Exocytosis (no cell damage)
What is an example of a merocrine gland
Goblet cells
Salivary glands
Pancrease
Sweat glands
What is the other type of exocrine secretion
Holocrine = Cell matures and dies to release product
What type of exocrine secretion is associated with odour
Holocrine
What is an example of a holocrine gland
Sebaceous glands
Tarsal glands of eyelid
What type of secretion causes minimal cell damage, has come cytoplasm and membranes, associated with orour
Apocrine gland
What is an example of aopcrine gland secretions
Lactating mammary glands
some adult sweat glands
External auditory canal
Ciliary glands in eyelid
What are the different types of secretions of exocrine glands
Merocrine
Holocrine
Apocrine
What is the smallest division of a gland
Acinus
What is a small group of serous cells attached to a mucus acinus
Serous Demilune
What is a contractile cells with epithelial origin
Myoeputhelial cells
Where are Myoepithelial cells found
Salivary glands
Sweat glands
Lacrimal glands
What do serous glands produce
Serous fluid
What are the characteristics of a serous gland
Cell are trapazoid shaped
Nucleus is round + noticeable
Cells pick up stain
What is an example of a serous gland
Pancrease
Parotid gland
Cheif cells in stomach
What does a mucus gland produce
Mucus
What are the characteristics of a Mucus gland
Cell stain light
Nucleus is flat + peripheral
What are some mucus glands
Goblet cells
Minor salivary glands of tongue
What do mixed glands produce
Serous + mucus
What are examples of mixed glands
Sublingual gland
Submandibular gland
What is a paracrine secretion
Signaling cell is close to target cell (hormone doesn’t enter blood)
What is Autocrine secretion
Signaling cell is its own target
What regulate endocrine secretions
Hormonal (-/+ feedback)
Autonomic NS