Anatomical Terms/Epithelial Tissue Flashcards
Superior
toward the head end or upper part of a structure or the body
ex: The head is ______ to the abdomen
inferior
toward the lower part of the structure or the body or away from the head end ; below
ex. The intestines are _____ to the liver
medial
toward or at the midline of the body; on the inner side of
ex. The heart is _____ to the lungs.
lateral
Away from the midline of the body; on the outer side of
ex. the thumb is _____ to the pinky.
proximal
closer to the origin of the body part or the point of attachment of a limb to the body trunk.
ex. The elbow is _____ to the wrist.
Distal
Farther from the origin of the body part or the point of attachment of a limb to the body trunk.
ex. The knee is _____ to the thigh
ipsilateral
on the same side
ex. The right had and the right foot are ________.
Contralateral
On opposite sides
ex. The right hand and left foot are contralateral.
anterior
in front of, toward the front
posterior
behind, toward the back
cranial
toward the head end
caudal
toward the tail end
rostral
toward the nose
deep
toward the inside, under the stucture
superficial
toward the outside surface, above another structure
prone
facing down or rearward (as in the palms or the body)
supine
Facing up or forward (as in the palms or the body)
afferent
conducting toward
efferect
conducting away from
necrosis
bad cell death
- some sort of pathology or something going on went wrong
apoptosis
- good cell death
- we need aging cells or worn out cells to die off so new ones can form and replace them
neoplasia
abnormal proliferation; cells dividing way too quickly or in a weird way
four tissue types:
- epithelial tissue
- connective tissue
- Muscle tissue
- nervous tissue
functions of epithelial tissue
- protection
- sensation
- control permeability
- secretions
- simple diffusion
- absorption- transcellular transport
- surface parallel transport
Apicial Surface
- this means toward the open area
- in an organ this is toward the lumen
- has microvilli and cilia
Purpose of microvilli for apical surface
- maximizes surface area
- transcellular transport
transcellular transport
absorbing something into the cell and transporting it through the cell and out through the basal aspect toward the basement membrane
Purpose of cilia for apical surface
- highly motile
- perform surface parallel transport
- nothing to do with absorption*
surface parallel tranport
is is the movement of things through the lumen using the cilia on the cells to propel it forward over the apical surface (does not go through the apical, it is not absorption)
why is there things established to maintain the integrity of the epithelium
it is exposed to many different harsh environments and needs to be able to respond to stress well
how does the integrity of the epithelium get maintained
- attachment to the basement membrane
- intercellular connections
- epithelial maintenance and renewal
Basal vs. apical
apical is toward the open area
basal is toward the underlying tissues
what does the basement membrane do for integrity
-anchors the epithelial tissue to the underlying tissues
intercellular junctions
- four types used to maintain integrity
1. tight junctions
2. adhering junctions
3. desmosomes
4. gap junctions*** (do not assist with maintaining integrity of epithelial tissue)
tight junctions
- these are the gate keepers
- they stop things from going between the cells that should be absorbed
adhering junctions
- these are for support and stability
- they act like a belt and they hold cells together
desmosomes
- these are for support and stability
- these act like snap buttons that pull together cells and stop them from being pulled apart
gap junctions
-easy cell to cell communication (do not assist with maintaining integrity of epithelial tissue)
what is key to survival of epithelial tissue
- regeneration is key!
- this is super important due to the harsh environments within the body
- some regeneration can occur in just 3-5 days!
Why can rapid regeneration also make epithelial cells more vulnerable
-this can lead to carcinoma or metaplasia which can affect the ability of the epithelial tissue to work properly
carcinoma
malignant tumor of epithelia
can also be from a gland which would be adenocarcinoma. adeno = gland
metaplasia
normal epithelia from one area replaced by another form of epithelia not typical for that region
what is bad about metaplasia in the respiratory tract
- this can lead to lack of function because if it is replaced with squamous metaplasia then there will be less cilia and the body won’t be abel to naturally get the mucous out.
- Additionally when the wrong type of tissue is in the wrong place then it is more likely to regenerate incorrectly.
Glands
- derived form epithelia
- can be individual cells or multicellular organs
- perform secretory function
exocrine glands
these are glands that secrete their products through ducts to the epithelial surface
goblet cells
- unicellular exocrine gland
- produces mucin
- part of the cell itself acts as a duct
mucin
- this is used to make mucus
- mucin + water = mucus (protects and lubricates internal body surfaces
endocrine glands
ductless glands that produce and secrete hormones into the blood stream
- secretion from endocrine can be humoral, neural, or hormonal
- endocrine organs are highly vascularized
humoral secretion
different substance levels in the blood regulate the secretion of hormones
neural secretion
when a nerve impulse causes a hormone to be released
hormonal secretion
when one hormone causes a gland to secrete another hormone
Connective Tissue (CT)
- most abundant and diverse of the four tissue types
- composed of some cells and lots of extracellular matrix
- different CT are composed of different cell types
fibroblasts
these are the cells in “proper connective tissue”
-these produce protein fibers and ground substance and put in extracellular space
what makes the extracellular matrix
this is produced by the cells of that connective tissue
extracellular matrix
is made up of ground substance and protein fibers
connective tissue proper
this is the general category for the different types of connective tissues
-can be divided into dense connective tissue and loose connective tissue
ground substance
found between fibers and cells of CT
-made of water salts and other substances
what do the protein fibers do
these provide support to the Extracellular matrix
- three types:
1. elastic
2. collagen
3. reticular
elastic fibers
these allow structures to stretch and recoil
collagen fibers
- these are very strong and flexible
- provide strength
- these are found in our tendons
reticular fibers
- found in organs where we need alot of space but still need support
- allows for blood vessels to transfer through
loose connective tissue
three types:
- areolar CT
- adipose CT
- reticular CT
areolar CT
Used to fill space within the body
- a loose connective tissue
- widely distributed
- highly vascularized
- contains all three fiber types
adipose CT
Functions: --provides fuel --insulates the body --stores energy, water, vitamins, hormones --supports and protects organs (adipocytes "fat cells") (highly vascularized)
reticular CT
Network of reticular fibers in loose ground substance
- used to create a scaffolding within a cell to allow space within a cell
- it makes a soft internal skeleton that supports the other cell types
Dense connective tissue
three types:
- regular CT
- irregular CT
- elastic CT
Dense regular CT
*made of parallel collagen fibers
can resist force in one direction
- important in tendons so they can resist the force of the muscle pull (since they only pull in one direction)
Dense irregular CT
*mainly made of thick collagen fibers in a random arrangement
can resist force in multiple directions
-important for places around joints (pericardium in cartilage) because there is pressure in many directions when joint move
elastic CT
- made of mainly elastic fibers
- can stretch and recoil
- important in blood vessels to allow them to hold blood and recoil to push blood
Cell Shape
Squamous:
Cuboidal:
Columnar:
layering
- simple
- stratified
simple
- One layering of cells that cover the basement membrane
- These are thin and fragile and are found in protected areas within the body
- Typically tend to be found where secretion, absorption and filtration occurs
stratified
- This is two or more layers of cells (and cell height between layers can differ
- They are stronger and thicker than simple
- They are found where chemical stresses are common or severe
squamous
thin, flat and irregular in shape
cubodial
- These are hexagonal boxes that often appear square
* They have a height and width that appear to be the same
columnar
- These have a hexagonal cross section
* Their height is greater than their width
simple squamous
Most delicate type in the body
Found in the skin, lining of the capillaries, and lines the pleural and peritoneal cavities
simple cuboidal
These provide limited protection and are involved in secretion and absorption
found in the pancreas, salivary glands and the kidney collecting ducts
simple columnar
Provides slightly more protection than simple cuboidal
Found in the uterine tubes, stomach, and intestinal track
stratified squamous
These occur where stresses occur
Can be keratinized or non keratinized
Found in the oral cavity, vagina, esophagus
stratified cuboidal
These are rare
Allow for selective absorption and secretion
Found in the sweat glands, mamillary glands, and salivary glands
stratified columnar
Rare/ allows for secretion and protects
These are found in the urethra, ducts of glands, pharynx
Pseudostratified ciliated columnar
All of the cells are attached to the basement membrane, so it is SIMPLE
The surface of the cells possess cilia
Lines the trachea and upper respiratory tract
help trap and transport particles that are found in the respiratory track
transitional epithelium
This is a stratified epithelium that can stretch without damaging the cells
Lines the bladder, urethra, and ureters
