My Histology Flashcards
Where would you find simple squamous epithelium?
Alveoli in lungs
Lining of heart, blood vessels and lymphatic vessels
What is the main function of simple squamous epithelium?
Allows materials to pass through by diffusion and filtration
Secretes lubricating substance
Where would you find simple cubodial epithelium?
In ducts and secretory portions of small glands
Kidney tubules
What is the main function of simple cubodial epithelium?
to secrete and absorb
Where would you find simple columnar epithelium?
Ciliated tissues – bronchi, uterine tubes and uterus
Non-ciliated – digestive tract and bladder
What is the main function of simple columnar epithelium?
To also absorb and also secrete mucous and enzymes
Where would you find psuedostratified columnar epithelium?
Ciliated - in respiratory epithelia
Function of psuedostratified columnar epithelium
Secretes mucous
Ciliated tissue moves mucous
Where would you find stratfied squamous epithelium?
Oesophagus
Mouth
Vagina
What is the function of stratified squamous epithelia
Protects against abrasion
Where would you find stratified cuboidal epithelium?
Sweat glands
Salivary glands
Mammary glands
What is the main function of stratified cuboidal epithelium?
Protective tissue
Where would you find stratified columnar epithelium?
Male urethra
Ducts of some glands
What is the function of stratified columnar epithelium?
Secretion and protection
Where would you find Transitional (urothelium)?
Bladder
Urethra
Ureters
What is the main function of transitional urothelium?
Allows urinary organs to expand and stretch
What things does Haematxylin and Eosin stain? What colours are these?
Most common
Haematoxylin – stains acidic structures e.g. nuclei, ribosomes, rough ER, DNA, RNA PURPLE
Eosin – stains basic structures e.g. proteins PINK
What stain would you use to deteich the presence of iron in biological tissues?
Pearl’s Prussian blue
What does Nissl Methylene blue stain?
Stains rough ER in neurons = Nissl substance
What does Massons trichrome stain?
Connective tissue technique Collagen stain Nuclei and basophils Collagen Cytoplasm, muscle, erythrocytes, keratin
Used to stain Periodic Acid Schiff
good at staining GLYCOGEN
used to stain specific ceullular compartments, and complex carbs as well as mucin (from from goblet cells of gastro and respiratory basement membranes, brush borders of kidney tubules, small and large intestine
What does Osmium stain for
Heavy metal stain
Stains for lipids
Identifying myelinated neurons
Where are primordial follciles loctaed?
The periphery of the cortex
Waht does FSH cause in the Grannulosa cells?
FSH causes grannulosa to change from squamous cells to columnar
What is the deepest layer of the endometrium?
Stratum basalis
What is the Superficial part of the endometrium?
Straum spongious
What changes can you see in the endometrium during the proliferative stage?
Stimulation of proliferating glands
Mitotic activity
Stroma cells are spindled and compact
What changes can you see in the endometrium during the Secretory stage?
Early Only SUB nuclear vacuoles with glycogen, Coiled Glands
Mid
Tortuous glands
Vacuoles ABOVE AND BELOW the nucleus.
GLANDS ARE MORE ROUNDED
Late- Saw Tooth Glands
Spiral arteries, intraluminal secretions
Blood vessels: What is the Tunica intima? In what vessels do you see it?
Its an endothelium, with basement membrane and connective tissue
See in all blood vessels
Blood vessels: What is the Internal elastic lamina? In what vessels do you see it?
Fenestrated layer of elastin
Hard to see in large elastic vessels as tunica media has many layers of elastin
Seen in both elastic and muscular arteries, and arterioles
Blood vessels: What is the Tunica media? In what vessels do you see it?
Smooth muscle Collagen Elastin Thick compared to tunica intima Seen in both elastic and muscular arteries, and arterioles and veins
Blood vessels: What is the External elastic lamina? In what vessels do you see it?
Less defined layer of elastin
Only seen in Elastic and muscular arteries
Blood vessels: What is the Tunica adventita? In what vessels do you see it?
TITET
Layer of supporting tissue composed of collagen
Nerve innervation
Blood supply (vasa vasorum)
Continuous with surrounding tissue
Seen in arteries, arterioles, veins, venules, but not capillaries
TITET
What is the epithelial lining in the trachea and bronchus?
Pseudostratified columnar ciliated
What is the epithelial lining in the Bronchioles?
Simple cudbodail, still ciliated
What is the epithelial lining in the alveoli?
Simple squamous epithelial cells
What Pneumocyte is bigger? Type 1 or 2
Is there a larger population of type 1 or 2?
Type 1 is Flattened, thin as possible - Makes up most of the surface area, but only 40% of the population
Type 2 is bigger 60% of the population, but 10% surface area
What is the role/features of type 1 pneumocytes
○ Flattened
Thin as possible, and contain few organelles
===> 90% surface area, 40% population
What is the role/features of type 2 pneumocytes
○ Bigger
○ 60% popuation, 10% surface area
○ Rounded cells, with round nucleus
○ Rich in mitochondria, smooth and rough ER
○ PRODUCE SURFACTANT - LOWERS SURFACE TENSION OF LUNGS. Like inflating lungs
§ Made at 28 weeks
How many cell layers are there in the air blood barrier? What makes up the air blood barrier?
2 cells layers in the air blood barrier!
Type I Pneumonocyte, resting on basement membrane, shared with RBC
Histolgy of the heart: what is the name of the loose fibrous tissue between the muscle fibres?
Endomysium. It stains/appear white inbetween the striated red cardiac nuclei
State some features of cardiac muscle:
Thickest layer of teh heart, the myocardium. Striated, with central nuclei, Branches off, and connected by intercalated discs (see pictire
What is the epithelium of the nasopharynx?
Respiratory epithelium
What is the epithelium of the vocal chords?
thin, stratified squamous epithelium over irregular fibrous tissue
• Reinkes space
What is the epithelium of the nose/nasal cavity?
• Keratinising (where fit finger in) non keratinising squamous epithelium (further up where you cant
* Nasal cavity line by respiratory epithelium * Loose fibrous connective tissue with Seromucous glands to produce snot, and lots of blood vessels
What is the epithelium of the mouth lining?
STRATIFIED SQUAMOUS EPITHILIUM, KERITIANISED.
What is the epithelium of the oesphagus?
Contains Longitudinal and circular layers of muscle
STRATIFIED SQUAMOUS EPITHILIUM
Also has submucosal glands - Secretes mucus to lubricate the food when swallowed
What is the epithelium of the false vocal folds?
upper - respiratory epithelium
What is the epithelium of the true vocal folds?
lower - stratified squamous epithelium
What is the epithelium of the vestibule (the area between true and false vocal folds)?
respiratory epithelium
What is the epithelium of the bile ducts?
Lined simple cuboidal - to - columnar epithelium, on basement
Height epithelial cell lining the duct increase as size of duct increase
What is the epithelium of the Gall bladder?
Gallbladder concentrates bile by removing water
Simple columnar epithelium, sitting on basement membrane, on specialised mucosa of connective tissue
Has Microvilli!!!
What is the lamina propria?
The lamina propria is a thin layer of connective tissue that FORMS PART OF THE MOIST LININGS known as mucous membranes or mucosa, which line various tubes in the body, such as the respiratory tract, the gastrointestinal tract, and the urogenital tract.
What is the epithelium in the PCT?
Simple Cuboidal
Features a brush boarder with microvilli
Lots of mitochondria so appears eosinophillic
What is the epithelium in the THIN segment of the loop of henule?
Simple squamous
What is the epithelium in the THICK segment of the loop of henule?
low cubodial
What is the epithelium in the DCT?
What does it secrete?
- The distal convoluted tubule has low cuboidal epithelium and has no brush border
- It is also much shorter than the proximal ct so it will often look like there are less present when really it’s the same amount
- The proximal ct contain lots of mitochondria too and so have an eosinophillic cytoplasm
- Distal convoluted tuble make the urine acidic and are important for regulaing acid base balance
- It secrets H+ ions and absorbs HCO3-
What are the 3 layers of the uterus?
Outer serosa
Myometrium
Endometrium
what are the 3 muscle layers in the myometrium?
longitudinal, Circular, then longitudinal smooth muscle again
What is the lining of the endocervix?
Simple columnar ciliated epithelium
What is the lining of the ectocervix?
non keratinising stratified squamous epithelium
What is the lining of the vagina?
non keratinising stratified squamous epithelium (same as ectocerix)
What are the histological characteristics of the endometrium in the proliferative phase?
Straight glands, no secretions. Stromal and epithelial mitoses.
What are the histological characteristics of the endometrium in the early secretory phase?
Coiling of glands and subnuclear glycogen vacuoles.
What changes happen to the endometrium in the secretory phase?
It becomes a secretory tissue: endometrial glands are coiled and filled with glycogen, blood vessels become more numerous and spiralled. Progesterone also inhibits myometrial contractions to ensure that
a fertilized egg can safely implant once it arrives in the uterus.
What are the histological characteristics of the endometrium in the late-secretory phase?
Prominent spiral arteries and decidualised stroma.
SAW-TOOTH GLANDS with more intraluminal secretions
More secretions and elongated glands.
What are the histological characteristics of the endometrium in the mid-secretory phase?
Tortuous glands, vacuoles above and below the nucleus, stroma-oedema and secretions.
Glands are more rounded
What are the acinus in the pancreas lined with?
Low cuboidal epithelium
What is the epithelium of the Proximal and distal part of the penile urethra?
Proximal part of penile urethra = pseudostratified columnar epithelium
distal part of penile urethra = non-keratinising stratified squamous epithelium
What is the epithelial lining of the stomach?
Simple columnar epithelium
do the bronchioles have hyaline cartilage?
no. They do have a prominent band of smooth muscle though
What are the traits seen in the:
Duodenum
Jejunum
Ileum
Duodenum -relatively smooth lining with few plicae circularis, relatively few goblet cells - Contains BRUNNER’S glands, secrete alkaline mucous
Jejunum - CLOSE PACKED plicae circularis, long and narrow villi. Many goblet cells
ileum - plicae circularis are not as closely packed as jejunum, Goblet cell numbers increased towards the end. Have peyers patches that occupy not only the lamina propria but also penetrate the muscularis mucosa to occupy the submucosa
What layer of skin is only found in the sole of feet and palms?
Next layer up is the Stratum Lucidum, 2-3 cell layers thick
Translucent, full of dead keratinocytes
Only found in thick skin, like palm and soles of feet
What is the layer of the skin where keratinocytes flatten out and die?
Stratum Granulosum 3-5 cell layers thick
This is where Keratinocytes FLATTEN OUT AND DIE. Creates Epidermal Skin barrier, Glycolipids are secreted out and cement them together
What layer of epidermis has immune cells?
Stratum Spinosum 8 - 10 cell layers thick,
Has dendritic cells, that immune cells looking for invading microbes
What layer of the skin has Melanocytes? What do melanocytes do?
The Stratum Basale also contain Melanocytes , which secrete Melanin
- The melanin in the melaoncytes is stored In Melanosomes
What are corneocytes?
Corneocytes are terminally differentiated keratinocytes and compose most of the stratum corneum, the outermost layer of the epidermis
Skin - What is the uppermost layer?
What is it made up of?
Stratum Corneum Uppermost Layer, 20-30 layers of skin
Glycolipid is the cement, Dead keratinised cells are the bricks
The dead Keratinised cells (corneocytes) secrete natural antibiotics
Made up of corneo-desmosomes
and desmosomes
- Corneo-desmosomes (known as adhesion molecules) keep the
corneocytes together
what is the epithelium of the tongue on its
a) ventral surface
b) dorsal surface
a) - ventral = non keratinised stratified squamous epithelium
b) - dorsal = keratinised stratified squamous epithelium
what is the epithelium of the mouth?
What about the Lips?
Mostly SSNK epithelium, but keratinised areas are common at sites of abrasion
Lips are Stratified squamous Keratinised epithelium
What is the epithelium of the peritoneal cavity and the pleural cavity
Simple squamous Mesothelium
What is type 3 collagen also known as ?
Reticulin
TISSUE OF RETICULO-ENDOTHELIAL SYSTEM ie. lymph nodes, spleen, liver
Can be seen with a silver stain
3 types of cartilage and where they’re found?
Hyaline- trachea, SYNOVAIL JOINTS
Elastic- epiglottis and pinna of the ear
Fibrous- intervertebral discs
Give type types of collagen and examples
Type I - Skin, bone, teeth, capsules of organs
Type II – Cartilage
Type III - Liver, kidney, spleen, arteries, uterus. Type III is also called reticulin.
Type IV - Basement membranes – most important to remember
Type V - Placenta
Describe how antibodies are specific to one antigen.
Antibodies are bound to antigens via the variable region (1)
- The variable region determines the specificity of the antibody to the different
amino acids that it contains, which change the shape of the antigen binding
site (1)
What colour stain for….
Periodic acid Schiff with sugars
Pink / magenta
What colour stain for….
Van Grieson with elastics
brown
What colour stain for….
Alcian blue with mucin
blue
What colour stain for….
Perl’s stain with iron
blue
What are the two organs lipofuscin is most abundant in?
Liver and heart
it is orange/brown colour
What are the two types of adipose tissue?
Brown adipose tissue (1), White adipose tissue (1)
What is the function of brown adipose tissue in a new born?
Thermoregulation
What is a feature of smooth muscle
Non striated
Fibres alot shorter than skeletal muscle fibres
single shaped nucleus
Lacks troponin
What is a feature of skeletal muscle
striated under voluntary control. Mulitnucleated muscle fibres nuclei that are not central Non branching
What is a feature of cardiac muscle
Branching fibres
Centrally located nucleus (occasionally two nuclei per cell)
gap junctions
intercalated discs
What is the name of the gaps in
between alveoli that allow the lungs to inflate equally?
Pores of Kohn
small communication pathways between alveoli, providing a collateral
pathway to reduce resistance and allow equal inflation of the alveoli.
What are clara cells, where are they found?
Clara cells are nonciliated bronchiolar secretory cells in the airway -
