what does epithelial tissue form

glands

what does connective tissue do

fill internal space
supports other tissue
transport materials
stores energy

what is the specialty of muscle tissue

contraction

what are the three types of muscle tissue

skeletal tissue
cardiac muscle
smooth muscle ( walls of hollow organs

what does neural tissue do

carry electrical signals from one part of the body to another

what is epithelia

layers of cells covering internal or external surfaces

what are glands

structures that produce sereations

what are characteristics of epithelia

cellularity (cell junctions)
polarity (apical and basal surfaces)
attachment (basement membrane or basal lamina)
avascularity
regeneration

how does epithelia get its nutrients

it diffuses in from the basolateral

what can epithelia do faster than any other type of tissue

reproduce and regrow

are all epithelia ciliated ?

no

what are the functons of epithelial tissue

provide physical protection
control permeability
provide sensation
produce specialized secretions (glandular epithelium )

what are three specializations of epithelial cells

1. move fluids over the epithelium (protection)
2. move fluids through the epithelium (permeability)
3. produce secretions (protection and messengers)

what increases absorption or secretion of apical sufaces

microvilli

what moves fluid on the apical surface

cilia

what three things help maintain the physical integrity of an epithelium

intercellular connections
attachment to the basement membrane
epithelial maintenance and repair

what are CAMs (cell adhesion molecules)

transmembrane proteins that bind to each other and to extracellular material

what is the intercellular cement

protoglycans

what is hyaluronan (hyaluronic acid)

a glycosaminoglycan that bond a thin layer of proteoglycans

what are cell junctions and what are the three types

specialized areas of the plasma membrane that attach a cell to another cell or to extracellular materials. the three types:
tight junctions
gap junctions
desmosomes

what is a tight junctions

when lipid portion of the two plasma membrane are tightly bound together by interlocking membrane proteins. they are so tight they cant prevent passage of water and can isolate wastes in the lumen

where is an adhesion belt and what does it do

inferior to the tight junction and it forms a band that encircles cells and binds them to their neighbors. they are attached to the microfilaments of the terminal web

what are gap junctions

holds two cells together by interlocking transmembrane proteins called connexons. form narrow passageway that lets small molecules and ions pass from cell to cell

where are gap junctions common

among epithelial cells and other tissues

what do gap junctions do in the heart

coordinate contractions in heart muscle

what are desmosomes

here CAMs and proteoglycans link the opposing plasma membranes. they are strong and can resist stretching and twisting

describe the typical desmosome

formed by two cells, ad within each cell is a dense area which is connected to the cytoskeleton and this gives it its strength.

where are desmosomes abundant

between cells in the superficial layers of the skin (that is why damaged skin is lost in sheets)

what are the two types of desmosomes

spot desmosomes
hemidesmosomes

what are spot desmosomes

small discs connected to bans of intermediate filaments. stabilize the shape of the cell

what are the hemidesmosomes

attach a cell to extracellular filaments in the basement membrane. helps stabilize position of epithelial cell and anchor it to underlying tissues

what are the two parts of the basement membrane

clear layer and the dense layer

describe the clear layer

closer to the epithelium, contains glycoprotiens and a network of fine protein filaments. secreted by epithelia. barrier to protein (thin)

describe the dense layer

contains bundles of coarse protein fibers produced by connective tissue cells. thick fibers , produced by connected tissue, strength and filtration

how are epithelia are replaced

by division of germinative cells (stems cells) -located near the basement membrane

how are epthelia classified

by shape and layers

what are the three shapes of epithelia

squamous
cubodial
columnar

what are the two layer types of epithelia

simple
stratified

what are the four types of squamous epithelia

-simple squamous epithelium
-mesothelium
-endothelium
stratified squamous epithelium

what does simple squamous epithelia do

absorb and diffuse

what does mesothelium do and where is it

lines body cavities and it is in the middle and does not communicate with the outside world

what is the endothelium

it lines heart and blood vessels and does not communicate with the outside world

what is stratified squamous epithelium

generally located where mechanical stresses are severe and they form several layers. they protect against attacks. keratin protein adds strength and water resistance (keratinized) . non keratinized resist abrasion but will dry out and deteriorate unless kept moist.

what does simple cubodial epithelia provide

limited protection and occurs where secretion or absorption take place

where is stratified cubodial epithelia founded

along the ducts of sweat glands and in the larger ducts of mammary glands

what is transitional epithelia

an unusual stratified epithelium because, unlike most epithelia, it tolerates repeated cycles of stretching and recoiling without damage. the appearance changes as stretching occurs. (in urinary system)

where is simple columnar epithelium chemical stress typically found

where absorption and secretion occurs (like in the small intestine) and can protect against

what is pseudostratified columnar epithelium and what does it typically have?

a columnar epithelium that includes several types of cells with varying shapes and functions. they nucleus are not aligned giving the appearance of being stratified but they are not. they typically have cilia (ex:trachea)

what does stratified columnar epithelia do an where?

provides protection along potions of pharynx, epiglottis, anus, and urethra and a few large excretory ducts?

what do endocrine glands do

release their secretions into the interstitial fluid (no ducts)

what do exocrine glands do

release their secretions into ducts that open onto an epithelial surface

what are the three modes of secretions for glandular epithelia

merocrine
apocrine
holocrine

what is merocrine secretion and where is it produced? what is an example

product is released from secretory vesicles by exocytosis so nothing is lost. it is produced in the Golgi apparatus. an example are sweat glands

what is apocrine secretion and where is it produced? what is an example

involves the loss of cytoplasm as well as the secretory product when the apical portion of the cytoplasm becomes packed with secretory vesicles and is then shed. it is produced in the Golgi apparatus and an example are mammary glands

how are holocrine secretion released and how are they replaced? what is an example

the entire cell becomes packed with secretory products. they are released by cell bursting killing glands which are replaced my stem cells. an example is sebaceous glands

modes of glandular secreation diagram

how is mucus formed

mucin mixed with water

what are the three types of secretions

serous glands
mucous glands
mixed exocrine glands

what do serous glands secrete

watery solution that contain enzymes

what do mucous glands secrete

mucins that hydrate to form mucus

what do mixed exocrine glands contain

both serous and mucous glands

what is an unicellular gland and what is an example

one cell that secretes everything. the only example is the Mucous (goblet) cells which are scattered among epithelia. an example is in intestinal lining

what is the simplest multicellular exocrine gland

the a secretory sheet in which gland cells form an epithelium that released cretions into an inner compartment

what three things describe the structure of multicellular exocrine glands

the structure of the duct
the shape of the secretory portion of the gland
the relationship between the ducts and the glandular areas

what are the two structure types a duct can have

it can be simple if it has a single duct that does not divide on its way to the gland cell or it can be compound if the duct divides one or more times on its way to the gland cells

what are the two shapes the secretory portion of a gland can have/

they can be tubular (tube shaped) or alveolar / acinar if they form blind pockets

what are glands whose secretory cells form both tubes and pockets called

tubuoalveolar and tubuloacinar

what kind of a relationship can a duct and a glandular area have

they can be branched where several secretory areas share one duct

mulitcellular glands diagram

what does connective tissues do for epithelial tissue

connect it to the rest of the body

what three basic components of connective tissue

specialized cells
extracellular protein fibers
fluid extracellular ground substance

what makes up the matrix? what does the the matrix for connective tissue

the extracellular fibers and ground substance together. it makes up the majority of the volume and determines specialized functions

what are 6 functions of connective tissue

- establishing a structural framework for the body
- transporting fluid and dissolved materials
- protecting delicate organs
- supporting, surrounding, and interconnecting other types of tissue
- storing energy reserves, esecially in the form of triglycerides

what are the three general categories of connective tissue

- connective tissue proper
- fluid connective tissue
- supporting connective tissue

what does connective tissue include and what does it do

includes connective tissues with many types of cells and extracellular fibers in a syrupy ground substance. it connects and protects

what does fluid connective tissue have and what does it do

distinctive populations of cells suspended in a watery matrix that contains dissolved proteins. they transport

how do supporting connective tissues differ from connective tissue proper and what do they do

because they have a less diverse ell population and a matrix containing much more densely packed fibers. they give structural support

what are the two types of connective tissue proper?

loose connective tissue and dense connective tissue

what is loose connective tissue

packing materials of the body. they fill spaces between organs, cushion and stabilize specialized cells in many organs and support epithelia. they have more ground substance and fewer fibers
an example is fat (adipose tissue)

what is dense connective tissue?

most of the volume occupied by fibers and often contain collagenous tissues because fibers are the dominant type f fiber in the. ( less ground substance) an example is tendons

what are the 9 connective tissue proper ell populations

fibroblast
fibrocytes
adipocytes
mesenchymal cells
macrophages
mast cells
lymphocytes
microphages
melanocytes

what is the most abundant cell type and where is it found? whats it secrete? what does it help make

fibroblast
in all connective tissue proper
secrete proteins and hyaluronan
they help make ground substance gel

what is the second most abundant cell type and where is it found? whats does it do

fibrocytes
found in all c.t proper.
maintain fibers of connective tissue

what are adipocytes? where is it found?

fat cells. each cell stores a single large fat droplet. only found in loose c.t. proper

what are mesenchymal cells? where are they found and what do they differentiate into?

stem cells that respond to injury or infection. they are found in embryonic cells and stem cells so they can turn into anything. it is found in all c.t. proper. they differentiate into fibroblast and macophages

What do melanocytes do?

Synthesize and store the brown pigment melanin

What are the three types of connective tissue fibers?

Collagen, reticular, and elastic. They are all secreted by fibroblast and are specialized proteins

What is the most common fiber in connective tissue proper?

Collagen fibers

Describe collagen fibers.

Long straight and unbranched, strong and flexible, and resist force in one direction. They are thick and durable

What is an example of collagen fibers?

Tendons and ligaments

What is a network of interwoven fibers?

Reticular fibers

Describe reticular fibers.

Strong and flexible, resist force in many directions, stabilize functional cells and structures

What is an example of reticular fibers?

Sheaths around organs

Describe elastic fibers

Contain elastin, branched and wavy, and they return to original length after stretching. It is protein made by fibroblast. It is like a rubber band and it is very durable.

What is the ground substance of connective tissue?

A clear colorless and viscous thing that fills space between cells and slows pathogen movement and also protects

Is embryonic connective tissue found in adults?

No the cells are but Wharton’s jelly is not. we have the cells so we can heal when needed by we don’t have the jelly because we do not need to regenerate

What is the first connective tissue found in embryos?

Mesenchyme (embryonic stem cells)

What is the loose embryonic tissue called?

Mucous connective tissue

What is the “packing material” of the body?

Loose connective tissue

What are the three types of loose connective tissue found in adults?

Areolar, adipose, and reticular

What is the least specialized of the three loose connective tissues?

Areolar

Describe areolar c.t.:

open framework, viscous ground substance, elastic fibers, and holds blood vessels and capillary beds. They are not very complex

What is an example of areolar c.t.?

Under the skin

Describe adipose tissue.

Contains many adipocytes (fat cells)

What are the two types of adipose tissue?

White fat and brown fat.

Describe white fat.

Most common, stress fat, absorbs shocks, and slows heat loss

Describe brown fat.

More vascularized, adipocytes have many mitochondria, when stimulated by nervous system fat breakdown accelerates, releasing energy. It also absorbs energy from surrounding tissues

Which of the two types of adipose tissue is primarily found in adults? Which is found in infants?

White. Brown and it has more fat cells

Adipocytes do not divide. Instead what do they do?

They expand to store fat and shrink as fats are released.

What cells can divide and differentiate and why do they do it?

Mesenchymal cells. They do it to produce more fat cells when more storage is needed

Describe reticular fibers.

They provide support, they are complex and three- dimensional networks, they have supportive fibers and reticular organs.

What do the supportive fibers (stoma) support?

Functional cells (parenchyma)

What are the reticular organs?

Spleen, liver, lymph nodes, and bone marrow

What is dense connective tissue?

Connective tissue proper that is tightly packed with high numbers of collagen elastic fibers

What are the three types of dense connective tissues?

Dense regular, dense irregular, and elastic

Describe dense regular.

Tightly packed, parallel collagen fibers

What are three types of dense regular connective tissues and what do they connect?

Tendons- attach muscle to bone, ligaments- connect bone to bone and stabilize organs, and aponeuroses- attach in sheets to large, flat muscle

Describe dense irregular connective tissue.

Interwoven networks of collagen fibers. They are layered in skin, around cartilage, around bones, and form capsules around some organs

What is elastic tissue made of?

Elastic fibers

What does supporting connective tissue do?

Support soft tissue and body weight

What is cartilage and what is it for? A gel-type ground substance and it is for shock absorption and protection

A gel-type ground substance and it is for shock absorption and protection