Histology Flashcards
Which epithelia is most likely to be composed of simple cuboidal cells?
Ducts and tubules
- collecting tubules
- salivary and pancreatic secretory ducts
Which epithelia is most likely to be composed of simple cuboidal cells?
Absorptive surfaces = GI tract and stomach
Which filaments maintain the structure of mcirovilli?
Actin filaments
What are goblet cells?
They are modified columnar cells which secrete mucous
How do goblet cells stain with H and E stain?
Poorly due to mucous being ‘washed out’
Which epithelia is most likely to be composed of pseudostratified epithelia?
The respiratory tract
What filaments give cilia their shape and what is the arrangement of these filaments?
Cilia have a core or X20microtubules
Arranged of X9 pairs circling a central pair
What are the X4 main layers of the respiratory system?
State what each of these layers contains.
1) mucosa
= epithelium
= lamina propria
2) Submucosa
3) cartilage/smooth muscle
4) Adventitia
What type of epithelia are found in the respiratory tract?
Pseudostratified columnar epithelia with cilia and goblet cells
What type of epithelia are found in the oesophagus?
Stratified squamous epithelia (non-keratinising)
What type of epithelia does skin have?
Stratified squamous epithelia (keratinising)
What does keratinising mean?
How will these appear under microscopy?
It means the top layers are dead keratinised cells with no nuclei due to keratins being linked with disulphide bonds
Flat and thin
What is transitional epithelium?
Where is it found?
Epithelium that can be distended
Only found in the urinary tract
What colour is the connective tissue when stained?
Usually pale as it does not stain well and mainly consists of extra-cellular matrix
It’s few cells are highly scattered (fibroblasts)
In connective tissue, what is ground substance?
A watery gel of proteiglycans synthesised from glycosaminoglycans (GAG’s)
What is extracellular matrix?
Proteins embedded in the watery gel ground substance (GAG’s)
What are the main proteins found in the ECM?
Elastin
Collagen
Fibronectin
Laminin
What do fibroblasts do?
Synthesise ECM (ground substance) and collagen
Other than fibroblasts, what other cells are permanently found in connective tissue?
Adipose cells
What are the X3 types of connective tissue?
Give examples of each.
1) basal lamina
2) loose (areolar) = mesentery and hypodermis
3) dense
Dense connective tissue is further subdivided into?
Give examples of each.
1) regular
= tendon/ligament
2) irregular
= dermis of skin
Which appear thicker under microscopy, collagen or elastic fibres?
Collagen fibres
What would dense, regular connective tissue look like?
Parallel collagen fibre bundles with fibrocytes in between
What are tendons mainly made from?
Collagen fibres
Can skeletal muscle cells divide?
If not what overcomes this?
No
Satellite cells
What is the structure of muscle from sarcomeres to the whole muscle?
Sarcomeres
Multiple sarcomeres = myofibril
Multiple myofibrils = myofibre (muscle fibres)
Multiple muscle fibres are bound together into fascicles
Fascicles join to make the muscle
Which types of muscle does NOT have gap junctions?
Skeletal, the other X2 types do
What would you look for under microscopy to see skeletal muscle?
- striated cells
- multinucleate with nuclei at peripheries
What would you look for under microscopy to see cardiac muscle?
- uninucleate cells with centrally locates nuclei
- striated
- intercalated discs
What would you look for under microscopy to see smooth muscle?
- no striations
- uninucleate with centrally located nucleus
- spindle shaped cells (tapered ends)
What is the name of the connective tissue which capsules around cartilage?
Perichondrium
What cells are located in perichondrium and what do they do?
Fibroblasts which produce chondrocytes which themselves produce cartilage
What is growth called when it occurs from the outside in, as seen with chondrocytes synthesising cartilage?
A positional growth
Cartilage has X2 types of growth, what are these?
Apositional and interstitial growth