Histology Flashcards
What are the four types of tissue within the human body?
Epithelial, Connective, muscle, Nervous
What type of tissue forms glands covers the body’s surface and lines hollow organs, cavities, and ducts?
Epithelial
What type of tissue protects and supports the body/organs, binds organs together and store energy reserves as fat.
Connective
What type of tissue generates force to allow movement?
Muscle
What type of tissue is sensitive and responsive to changes in homeostasis by generating nerve impulses?
nervous
What are the 7 types of epithelial tissues?
Simple squamous Simple cuboidal Simple columnar Stratified squamous Stratified cuboidal Stratified columnar Pseudostratified columnar
Form influences _____
function
What type of junctions can epithelial use?
tight junctions
desmosomes
What is a tight junction and what is a notable feature of it
a specialized connection of two adjacent animal cell membranes such that the space usually lying between them is absent
Makes a very close connection. No liquids can get through.
What is a desmosome?
intercellular junctions that provide strong adhesion between cells
very strong junction attached with filiments
What is a gap junction?
a specialized intercellular connection between a multitude of animal cell-types. They directly connect the cytoplasm of two cells, which allows various molecules, ions and electrical impulses to directly pass through a regulated gate between cells.
Great for cells that need to communicate
What is the main purpose of epithelial tissue?
to serve as a cover or a lining
What supports epithelial tissue?
connective tissue via a Basement membrane
What are the two components of the basement layer?
The basal lamina
reticular lamina
Where are the capillaries of the epithelial tissue located?
epithelial tissue is avascular. There are no capillaries
Epithelial tissue is polar. What does this mean?
it has a top and a bottom
the apical surface - top
basal surface - bottom
is the basement layer part of the connective tissue?
no. it is the bridge between the Connective tissue and the epithelial tissue
What is the function of the basal lamina?
it is a non-cellular adhesive
What is the function of the reticular lamina? What is it composed of?
It is composed of collagen fibers belonging to the connective tissue below. It acts as a binder between the epithelial tissue and the connective tissue
Describe simple squamous epithelial tissue.
single layers of “fried eggs” often in a line
What is the function of simple squamous epithelial tissue?
Allows the diffusion of materials in sites where protection is not important.
Secretes lubricating substances in serosae
Where can simple squamous epithelial tissue be found?
Kidney glomeruli (filtration)
alveoli of the lungs - allows diffusion
in blood vessels-lines the inner vessel
in lymphatic vessels-lines the inner vessel
Describe simple cuboidal epithelial tissue
Small cubes with round nuclei
What is the function of simple cuboidal epithelial tissue
Secretion and absorption
Where can simple cuboidal epithelial tissue be found?
Kidney tubules
ducts
secretory portions of small glands
surface of the ovaries
describe simple columnar epithelial tissue
Rectangles with lined up nuclei
cilia or no cilia
what is the function of simple columnar epithelial tissue?
Absorption
mucus secretion
enzyme secretion
if ciliated it propels mucus by ciliary action
Where can simple columnar epithelial tissue be found?
if non-ciliated it can be found lining the GI tract, gallbladder, and ducts of some glands
if ciliated it can be found lining the bronchi, uterine tubes and some regions of the uterus
typically, how many layers thick is stratified cuboidal epithelial tissue?
two layers
Where can stratified cuboidal epithelial tissue be found?
some sweat glands and mammary glands
Where can stratified columnar epithelial tissue be found?
very limited distribution
fond in the pharynx
male urethra
and some glandular ducts
also occurs at transition areas between two types of epithelia
Describe pseudistratified columnar epithelial tissue.
elongated rectangles with non-linear nuclei with or without cilia
What is the function of pseudistratified columnar epithelial tissue?
secretion (particularly of mucus)
propulsion by cilia
Where can pseudistratified columnar epithelial tissue be found?
non-ciliated- in sperm carrying ducts and ducts of large glands
ciliated types- in trachea
mostly in the upper respiratory duct
Describe stratified squamous epithelial tissue
squished scales with many layers
What is the function of stratified squamous epithelial tissue?
protects underlying tissue in areas of abrasion.
where can stratified squamous epithelial tissue be found?
anywhere where friction is common.
If nonkeratinized- forms the moist lining of the esophagus, mouth, vagina
if keratinized- it forms the epidermis
describe transitional epithelium.
like stratified squamous layered on top of stratified cuboidal
surface cells resemble bubble shaped squamous cells either big bubbles or stretched depending on level is distention
What is the function of transitional epithelium?
specifically for areas that need to distend
where can transitional epithelium be found?
in the bladder
What is glandular epithelia?
epithelial tissue that secrets a particular product.
How is glandular epithelial tissue classified?
by site of release (endocrine or exocrine)
if it is uni or multi celluar
if a duct is present or not
What are the three major types of membranes?
Cutaneous-skin
mucous-digestive system and respiratory system
serous-body cavities
what is the most abundant type of tissue in the body?
Connective tissue
what is the function of connective tissue?
to support, defend, aid in movement, bind together, store, repair, transport and commpartmentalize
What are the two basic components of connective tissue?
sparse cells and a matrix
What is the matrix of connective tissue?
protein based material (fibers plus ground surface)
What are the four major types of connective tissue?
Connective tissue proper
cartilage
bone
blood
What are the two sub-classes of connective tissue proper?
Loose connective and Dense connective tissue
What are the three type of loose connective tissue?
Areolar
Adipose
Recticular
What are the three types of dense connective tissue?
Dense regular
Dense Irregular
Elastic
What are the three types of Cartilage?
Hyaline
Elastic
Fibrocartilage
What stem cell does all connective tissue start as.
Mesenchyme
What is the ground substance cell type in connective tissue.
What is it composed of?
the matrix.
contains water, salts, and proteoglycans along with adhesion proteins
What are the three types of fiber.
Collagen, elastic, reticular.
What does a cell ending in -blast mean?
that is it a young, still developing bud/germ of a cell
What does a cell ending in -cyte mean?
A mature cell
What are two adhesion proteins?
chondroitins and keratins
What the the usual 4 components of ground substance?
Water, Salts, proteoglycans and adhesion proteins
What is a matrix?
a mixture of fibers and ground substance
What is the dominate fiber type?
collagen
What is the function of collagen?
add flexible but resistant strength to a connective tissue.
Like a rope
What makes collagen cushiony?
it is absorbent and attracts water
Describe elastin
small in diameter than collagen
Dark
How elastic is elastin?
it can stretch 150% and still snap back
how does elastin spread?
it branches to form networks similar to spiderwebs
what are the 3 areas where elastin is most abundant?
skin, blood vessels, lungs
Describe reticular fibers and their formation pattern
Small, delicate collagen fibers surrounded by glycoprotein that form a “jungle gym”
Why is the formation pattern of reticular fiber important?
Because it creates a jungle gym lattice that allows optimal utilization of space. “ the floors in a tall building”
Where are two places that reticular fibers are found?
the stroma of soft organs
in the basement membrane of epithelial cells
What is scurvy and how does it relate to CT
scurvy is a severe vitamin c deficiency. Vitamin C is essential in the formation of collagen.
What are the three types of loose CT
Areolar, Adipose, Recticular
Areolar connective tissue contains a reservoir of ____&____ equal to the circulatory volume.
Water & Salts
function of Areolar CT
Binds and Pacts
Cushion
What is composed of areolar and adipose connective tissue?
the subcutaneous layer of the epidermis
What are the two fiber types located in areolar ct
Elastin
Collagen
What are the three main components of adipose tissue?
adipocytes-Lipid storage
Recticular fibers
Blood supply
What are the functions of adipose tissue?
Protection of organs
Energy storage
Insulation
Shock absorption
Where is adipose tissue found?
Armpits
Around the kidneys and eyes
Breasts
in the abdomen
Areolar tissue covers the ______ bundles
neurovascular
Describe Reticular tissue
Network of thin fibers
spiderweb of collagen fibers
Where is reticular fiber found?
bone marrow
stroma of spleen, lymphatic structures, and liver
What is the function of reticular fiber?
to support other cell types
can help to filter blood in spleen and lymph-nodes due to macrophages
what are macrophages?
cells that roam connective tissue, eat dead cells, detect invaders them stem from white blood cells
what are fibroblasts?
large fusiform cells that produce fiber and ground substance
leukocytes are also known as _
white blood cells
What are plasma cells?
they synthesize antibodies
What are mast cells
cells found among blood vessels that produce heparin and histamine
What are four names for the gel of the matrix?
Ground substance, tissue fluid, extracellular fluid, interstitial fluid.
What are the three primary germ layers during embryonic development?
Ectoderm
mesoderm
endoderm
What does the ectoderm eventually become?
epidermis, nervous system
What does the endoderm eventually become?
Mucous membranes of resp. and digestive systems
What doe the mesoderm eventually become?
mesenchyme
What is mesenchyme?
The stem cells that all connective tissue comes from
most gland tissues are composed of___?
Epithelial tissue
____tissue lines the body cavities and internal/external linings of may organs
Epithelial tissue
How does epithelial tissue protect?
From abrasion, acts as a barrier from infection and internal acids
What are the 6 major functions of epithelial tissue?
PESAFS
Please excuse sally again for science
Protection excretion secretion absorption filtration sensation
What does ET secrete?
Mucus, sweat, enzymes, hormones
What does ET excrete?
Waste-CO2 from pulmonary ET
Bile from ET of the liver
What does ET absorb?
Chemicals from adjacent mediums
nutrients through the ET of the small intestines
What does ET filter?
Blood, urinary waste
How does ET give sensation?
Merkel cells that transmit to nerve endings
What lies between ET and CT?
basement membrane
What are three functions of the basement membrane?
ABC
Anchors
Binds growth factors to regulate development
Controls exchange of materal
Both ____ and ____ can develop goblet cells
Simple columnar
and pseudostratified columnar
What is the function of goblet cells?
they secrete products that form mucus when they mix with water
Where can simple squamous ET be found?
Alveoli of the lungs
inner lining of the heart and blood vessels
serous membranes of the stomach, intestines
golmerular capsules of the kidneys
some kidney tubules
surface mesothelium of pleura, paricardium, peritoneum etc
Where can simple columnar ET be found?
inner lining of the stomach, intestines, gallbladder, uterine tubes, uterus, some kidney tubuals
Where can pseudostratified columnar ET be found?
Respiratory tract from nasal cavity to the bronchi
portions of the male urethra
Where can keratinized Stratified squamous ET be found?
Epidermis
Where can non- keratinized Stratified squamous ET be found?
epidermis, tongue, oral mucosa, esophagus, anal canal, vagina
What can stratified cuboidal ET be found?
Sweat gland ducts, egg producing vesicles of ovaries, sperm producing ducts of testies
Where can transitional ET be found?
urinary bladder, parts of the ureter, bladder, and part of the urethra
What are the 8 functions of connective tissue
Thus I Simply Must Study Harder Because Poor
TISMSHBP
Transport Immune protection Storage movement support heat production binding of organs physical protection
What are the 6 cell types found in fibrous CT
FMLPMA
Fuck My Life Please Accept Me
Fibroblasts Macrophages Lymphocytes Plasma cells Mast cells Adipocytes
What are Fiboblasts
Large fusiform or stellate cells
produce fibers and ground substance
What are macrophages?
Large phagocytic cells
Wander through connective tissue
eat bacteria and dead cells
activated immune system when threats present themselves
What are Leukocytes?
two types
NL
White blood cells
neutrophils-attack bacteria
Lymphocytes-work against bacteria
What are plasma cells?
Cells that synthesize antibodies
What are mast cells?
cells that produce heparin and histamines
What are adipocytes?
fat cells
What are the three types of fiber found in Fibrous connective tissue.
Collagen fibers
Recticular fibers
Elastic fibers
What are collagenous fibers
fibers made of collagen
Rope like in structure
Flexible and strong
Most abundant
What are recticular fibers
Thin collagen fibers coated with glycoprotein
They form a sponge like framework for such organs as the spleen and lymphnodes
What are elastic fibers?
Thin dark fibers made of a protein called elastin.
stretch up to 150%
allow skin, lungs, arteries to stretch
What is ground substance?
the jello filler within a matrix. acts as a cushion for compression forces
