Histology Flashcards
What does surface epithelia cover ?
covers or lines surfaces, cavities and tubes
lines the gall bladder
What does apical mean ?
faces the lumen of a tube or the external environment
What does basal mean?
attaches to the basement membrane
At what state are the cells?
Cells usually polarised
What are the functions of epithelial cells ?
Mechanical barrier(skin)
Chemical barrier(lining of stomach
Absorption(lining of intestine)
Secretion(salivary gland
Containment(lining of urinary bladder
Locomotion(oviduct)
Sensation(neuroepithelium: taste buds)
What type of epithelial layers are there ?
Simple
Stratified(+2 layers)
Pseudostratified(multiple layers)
What are microvilli?
finger like projections at the apical end of cells that increase surface area
What are microvilli also called?
Brush border
Cilia is important in…
Movement of water
What do keratin proteins do?
keratin protein on tissue surface, improves strength of the cells
What are goblet cells?
they have nucleus in the bottom and are single cell mucous glands
What do glandular epithelia produce?
they produce secretory products: sweat, hormones, mucous, enzymes etc.
How do endocrine cells secrete their products ?
They secrete the products into the blood and the hormones are distributed by the vascular system
What are endocrine cells also called?
ductless glands
How do exocrine cells secrete their products ?
secrete their products onto a surface through a duct
what are exocrine cells also called?
ducted glands
What types of connective tissue are there ?
Embryonic
soft
hard
special
What are the 3 basic cell shapes found in covering epithelia ?
Squamous(flattened)
Cuboidal(Cube)
Columnar(tall and thin)
What are the 3 main types of layer structure for epithelia
Simple
Stratified
Pseudostratified
How are hormones distributed?
Via the vascular system
What counts as soft connective tissue?
tendons
mesentery
storm of organs
dermis of the skin
What type of soft connective tissues are there?
Loose
Dense
Reticular
Adipose
How can you define loose connective tissue?
loosely packed fibres separated by ground substance
How can you define dense connective tissue?
densely packed bundles of collagen fibres
What is “dense regular” tissue?
fibres aligned (tendon)
What is “dense irregular” tissue?
fibre bundles running in many directions (ligament)
What are the 3 types of cartilage?
hyaline
elastic
fibrocartilage
What is hard connective tissue?
Bone and Cartilage
What are some characteristics from hard connective tissue?
strong
flexible
compressible
semi-rigid tissue
Describe the matrix of HCT?
semi-rigid nature of matrix comes from highly hydrated nature of the ground substance
What do we mean by HCT being avascular?
no venous system directly to the cells, the cells receive their nutrients from diffusion through their matrix
What is the most common type of cartilage?
Hyaline cartilage
What is made of hyaline cartilage?
articular surfaces
tracheal rings
costal cartilage
epiphyseal growth plate
What is made of the outer shell of dense cortical bone?
the shaft(diaphyses)
What can bone be defined as ?
outer shell of cortical bone- dense areas without cavities
What occupies the end of a bone and what is it called?
Epiphyses and it is made out of cancellous and trabecular bones
What do cancellous/trabecular bones have?
numerous interconnecting cavities
What do bones contain?
Osteocytes
What is bone ?
bone is a living tissue that is being penetrated by small canals(aversion canal) where blood vessels and nerves go through
What is bone being penetrated by?
small canals aka aversion canal
What is a small canal called as well?
aversion canal
What goes through the aversion canal?
blood vessels and nerves
What are considered cells?
Osteocytes
Osteoblasts
Osteoclasts
What is considered extracellular matrix?
Organic matrix: collagen and glycoprotein
Inorganic matrix: calcium and minerals
What are osteons?
formations characteristic to mature bone
What are Chondrocytes?
metabolically active cells that synthesise and turn over a large volume of ECM
What does the extracellular matrix consist of ?
fibres: collagen, reticular and elastic fibres
What is the ground substance made of?
it is a gel-like material found between cells in connective tissues
It does not have a specific shape and is made up of large , chain-like sugar molecules called glycosaminoglycans(GAGs)
What do glycosaminoglycans do?
they attach to protein cores to form bigger molecules called proteoglycans
What is the function of the ground substance ?
this substance helps tissues stay hydrated, supports cells and allows nutrients to pass through.
It also acts like a cushion, protecting tissues from pressure or damage.
What is the ground substance also been described as ?
“filler” that keeps tissues flexible, strong and healthy