connective tissue - histo lec Flashcards
middle layer of embryo
Mesoderm:
: embryonic tissue
> stem tissue (point of origin) of all connective tissues
Mesenchyme
composition of ECM
GROUND SUBSTANCE
FIBERS: elongated polymerized proteins
colorless and transparent gel-like material
Ground substance
elongated polymerized proteins
GS component
FIBERS:
Major component of GS
glycosaminoglycogens (GAGs)
component of ECM that
- as lubricant
- helps prevents invasion of tissues by foreign agents
- resists forces of compression
ground substance
composition of GS (3)
glycosaminoglycans, proteoglycans and glycoproteins
Major GAGs (4)
Chondroitin sulfate, keratan sulfate, heparin sulfate, hyaluronic acid
made of multiadhesive proteins (fibronectin, integrins,laminin)
GS
multiadhesive proteins that form the GS
3
Fibronectin, integrins,laminin
FUNCTION OF multiadhesive proteins that form the GS
bind cells to fibers of CT
multi-adhesive protein of GS
- binding sites: cells, collagen fibers
- connects components of CT, attachment to cells
Fibronectin
multi-adhesive protein of GS
binding sites for cell membranes
-with collagen and entactinforms basal lamina
Laminin-
multi-adhesive protein of GS
–integral proteins of plasma membranes
-bind directly to collagen fibers
Integrins
Three Main Types OF FIBERS
Collagen
Reticular
Elastic
Types OF FIBERS
>most abundant fibrous protein; large fibers
Collagen
color of collagen in H&E stain
pink
color of collagen in Mallory’s trichrome
blue
color of collagen in Masson’s stain
green
type of fiber
great tensile strength (promote flexibility and strength)
collagen
made up of 3polypeptide chains in helix & cross-linked
tropocollagen
type of fiber
Not a single entity
collagen
there are _ types of collagen
20
–most common types of collagen; interstitial collagen
type I, type II, type III
Families of collagen:
a. fibrillar collagen –
e. other collagens –
types I, II, III, V, XI
Families of collagen:
b. facit collagen –
(fibril-associated collagen with interrupted triple helix) types IX, XII, XIV
Families of collagen:
c. short-chain collagens –
type VIII, X
Families of collagen:
d. basement membrane collagen –
type IV
families of collagen
e. other collagens –
rest of the collagen types
Collagen: 4 Categories accdg to structure and function
> Collagen Fibers: tendons, organs, and dermis
Collagens that form long Fibrils
Collagen: 4 Categories accdg to structure and function
> short structures; bind to surface of collagen fibrils
Fibril Associated Collagens
Collagen: 4 Categories accdg to structure and function
> Type VII: anchoring collagen
bind basal lamina to reticular fibers
Collagens that form Anchoring Fibrils
Collagen: 4 Categories accdg to structure and function
> Type IV Collagen: major structural component of the basal lamina
Collagen that form Networks
type of fiber
thinner and intermediate fibers made up of elastin and
fibrillin
elastic fibers
component of elastic fibers
organize secreted elastininto distinct elastic fibers
fibrillin–
component of elastic fibers
hydrophobic, rubber-like glycoprotein main component of elastic fibers
elastin
stain used for elastic fibers
resorcin-fuchsin stain
component of elastic fibers
form loose network
> branching fibers for stretch and recoil
elastic fibers
elastic fibers
may be stretched up to __ of their resting length
150%
type of fibers
interspersed with collagen
> seen in smooth muscle walls of elastic arteries, alveolar septa of the lungs
elastic fibers
type of fibers
> consists mainly of collagen TYPE III
reticular
type of fibers extremely thin (0.5-2.0 μm) > forms networks of very thin
reticular
type of fibers
>abundant in parenchymal cells of organs and hematopoietic organs
reticular
type of fibers
stain black with silver salts (not seen in H&E)
reticular
type of fibers
a.k.a. argyrophilic fibers
reticular
CT Cells
> cells that do not migrateand remain in the connective tissues
fibroblast, pericytes, adipose cells, mast cells
Fixed Cells
CT Cells
> remain temporarily in connective tissue
> use blood and lymph vascular system to relocate to regions of connective tissue
> macrophages, plasma cells, leukocytes
- Transient Cells
Fixed CT Cells
most common; synthesis and secretion of collagen fibers and ground substance of CT
fibroblast
Fixed CT Cells
Fusiform, tapering on both ends, Possess an oval nucleus
fibroblast
TYPE OF FIBROBLAST
–spindle-shaped, well developed RER and GA during matrix production.Myosin throughout the cytoplasm, actin and α-actininon the periphery (muscle contraction)
Active fibroblast
TYPE OF FIBROBLAST
–functions in wound contraction.
myofibroblast
TYPE OF FIBROBLAST
smaller, reduced RER, GA. Ribosomes abundant
Inactive fibroblast
Fixed CT Cells:
May give rise to fibroblast, endothelial cells, smooth muscle cells on injury
Pericytes
Fixed CT Cells:
Possess characteristics of endothelial cells and smooth muscle cells
Pericytes
Fixed CT Cells:
Smaller than fibroblast
Pericytes
Fixed CT Cells:
along capillaries lying in their own basal lamina
Pericytes
Fixed CT Cells:
Function as contractile cells that modify capillary blood flow
Pericytes
Fixed CT Cells:
Fully differentiated cells
Adipose cells
Fixed CT Cells:
Increase in number in early neonatal life
Adipose cells
Fixed CT Cells:
Synthesis, storage and release of fats
Adipose cells
aka white adipose cells
with single large fat droplet
cytoplasm and nucleus are queezedinto a thin rim around the cell’s periphery.
receptors for insulin, growth hormone, norepinephrine, glucocorticoids
Unilocularadipose cells
aka brown adipose cells)
smaller than white adipose cells
fat stored in many small fat droplets
spherical centrally located nucleus
Multilocular adipose cells
Fixed CT Cells:
Arise from myeloid stem cells in bone marrow
Mast Cells
Fixed CT Cells:
Usually reside near small blood vessels
central spherical nucleus, cytoplasmic granules “primary mediators”
Mast Cells
mediators released by mast cells
Vasodilator
histamine
mediators released by mast cells
Anticoagulant, inactivates histamine
heparin
mediators released by mast cells
Attractant for eosinophils
to site of inflammation
ECF
mediators released by mast cells
Attractant for neutrophils tosite of inflammation
NCF
mediators released by mast cells
Inactivateleukotriene C4
ARYL SULFATE
mediators released by mast cells
Increasesinflammatory responses
NEUTRAL PROTEASES
mediators released by mast cells
Inactivates
chondroitin sulfate
CT: Cell Components
motile phagocytes
> possess irregular surfaces (pleats, protrusions, indentations)
macrophage
CT: Cell Components
well developed organelles (Golgi, lysosomes, rER)
> maintenance of CT-Ig, C’, lysosomes,cytokines)
> histiocytes
macrophage
CT: Cell Components
>reticuloendothelial system (heterogenous phagocytic cells)
Mononuclear Phagocyte System
CT: Cell Components
vital stain of Mononuclear Phagocyte System
Trypan Blue
CT: Cell Components
isotopically labelled monoclonal Ab’sagainst surface markers
Mononuclear Phagocyte System
CT: Cell Components
monocytes, macrophages, alveolar phagocytes, Kupffercells, osteoblast, dendriticcells
Mononuclear Phagocyte System
CT: Cell Components
derived from B-cells activated by antigens
> large, ovoid cells, basophilic cytoplasm (rER)
plasma cells
: pale portion in the plasma cell (Golgi apparatus)
hof region
CT: Cell Components
>for production of antibodies (IgE)
plasma cell
CT: Cell Components
WBCs that migrate by diapedesis
> cellular defense
> implicated in inflammatory processes
leukocytes
> red fluid that circulates inside blood vessels
transport VEHICLE
transports oxygen, nutrients and other substance to all organs and tissues
gives LIFE
blood
ph of blood
pH 7.35-7.45
components of blood
Components:
> Formed Elements ( WBCs, RBCs, platelets)
> Fibers: form of fibrin
> Fluid Ground: Plasma
Stains used in blood smear
(Giemsa or Wright’s) containing azure dyes
> terminally differentiated (ANUCLEATED) Cells
contains an oxygen carrying molecule called hemoglobin
Biconcave shape (7.5um diameter)
Plasmalemma(band 3 protein, glycophorinA, spectrin, ankyrin)
RBC
Life Span of 120 Days
> Senescent ____ removed in the spleen, liver and BM
RBC
> spherical nucleated cells
> migrate to tissues to perform various activities
Leukocytes (WBCs)
Two Groups OF WBCs
> Granulocytes (Polymorphonuclear)
> Agranulocyes(Mononuclear)
> arise from a similar committed progenitor cell CFU-GM
AGRANULOCYTES (MONONUCLEAR)
> large off centered nucleus (kidney or U-shaped)
opaque, gray to blue cytoplasm
slightly condensed chromatin pattern
.> 2-10%
MONOCYTES
> spherical nuclei; scanty cytoplasm (slightly basophilic)
6-8um (small) 9-18um (large)
can return to the blood stream after diapedesis
LYMPHOCYTES
differentiated B cells; Absecretion
> abundant blue cytoplasm; clear zone; eccentric nucleus; light streaks/vacuoles
Plasma Cells
Produces antibodies and other chemicals responsible for destroying microorganisms
Contributes to allergic reaction, graft rejection, tumor control, and regulation of the immune system
Lymphocyte Functions
> anucleated, disk-like cell FRAGMENTS
> fragmentation of the MEGAKARYOCYTE
PLATELETS (THROMBOCYTES)
Megakaryocytes divide by
endomitosis
Platelets are rich in
GAGs and glycoproteins (adhesion)
Granules of the Granulomere
> Delta Granules (Electron dense): has ADP, ATP, serotonin
Alpha Granules (larger): platelet derived factor, PF4
Lambda Granules (lysosomalenzymesa)
Granules of granulomere
(Electron dense): has ADP, ATP, serotonin
Delta Granules
Granules of granulomere
platelet derived factor, PF4
Alpha
Granules of granulomere
lysosomal enzymes
Lambda granules
type of collagen
major structural component of the basal lamina
Type IV Collagen
type of adipose cells
receptors for insulin, growth hormone, norepinephrine, glucocorticoids
white adipose cells/unilocular
components of plasmalemma
> Plasmalemma(band 3 protein, glycophorinA, spectrin, ankyrin)
components of GAGs that are bound to protein
chondroitin sulfate
keratan sulfate
heparin sulfate
components of GAGs that are not bound to protein
hyaluronic acid
majority of CT is an ____________ phase
aqueous
aqueous phase of CT is also called
ground substance
component of GAGs not bound to protein
has high viscosity in aqueous solution
responsible for gel-like consistency
hyaluronic acid
together with ________, laminin forms basal lamina
collagen and entactin
reticular fibers consist mainly of type what collagen
Type III
Reticular fibers are abundant in: (2)
parenchymal cells
hematopoeitic organs
cells that move so that they converge on site of injury
free or transient cells
function of pericytes
contractile cells that modify capillary blood flow
pericytes give rise to what type of cells
endothelial
smooth muscle cells
fibroblasts
type of free cell that get rid of debris and dead cells
macrophage
a not specific system
replaced by mononuclear phagocyte system
reticuloendothelial system
is plasma cell basophilic or acidophilic
basophilic
passage of blood cells through walls of capillaries
diapedesis
3 divisions in centirfuged blood
plasma
buffy coat
RBC
buffy coat is composed of
WBC and platelet
percentage of plasma
55%
percentage of formed elements
45%
percentage of water in plasma
91%
percentage of blood proteins in plasma
7%
percentage of hormones, nutrients, enzymes in plasma
2%
polymorphonuclear cells are also called
granulocytes
mononuclear cells are also known as
agranulocytes
components of hemoglobin
heme and globin
protein part of hemoglobin
globin
nonprotein part of hemoglobin
heme
life span of rbcs
120 days
senescent rbcs are removed in
liver, spleen, BM
types of granulocytes based on stain
stain darkly
present at some level in all WBCs
azurophilic (primary)
types of granulocytes based on stain
responsible for staining reactions
specific/specialized granules
specific granules (secondary)
how many nuclei in neutrophil
2-5
color stain of neutrophil
pinkish or reddish purple
function of neutrophils (2)
bacterial defense through phagocytosis
release of specific granules for oxidative killing
pus
life span of pus in CT
1-4 days
cytoplasmic granules which stain RED
EOSINophil
Number of nuclei in eosinophil
2
percentage of neutrophil in WBC
60-70%
Percentage of eosinophil in WBC
2-4%
oval specific granules containing majorbasic protein
EOSINOPHIL
Functions of eosinophil (4)
Phagocytose Ag-Ab complexes
Cytotoxic effect on parasites
allergic reactions
lessen inflammatory response
cytoplasmic granules which stain blue to purple or metachromatically
basophils
cytoplasmic granules
least seen in blood smears
basophils
cytoplasmic granules
IgE is bound to surface
basophils
how many lobes in basophils
2 or more irregular lobes
basophil is similar in function with
mast cells
functions of basophils (2)
delayed hypersensitivity
immediate hypersensitivity
agranulocyte
opaque, gray to blue cytoplasm
monocyte
agranulocyte with slightly condensed chromatin pattern
monocyte
percentage of monocyte in WBCs
2-10%
agranulocyte which can return to blood stream after diapedesis
lymphocyte
groups of lymphocytes
T cells
B cells
NK cells
lymphocyte functions
Produces antibodies and other chemicals responsible for destroying microorganisms
Contributes to allergic reaction, graft rejection, tumor control, and regulation of the immune system
Platelets appear in
clumps
zone of platelet
lightly stained; peripheral zone
Hyalomere
zone of platelet
darker; central zone
Granulomere
FUNCTION of Platelets
maintaining the integrity of blood vessels
forming hemostatic plugs to stop blood loss from injured vessels and, in the process,
promoting coagulation of plasma factors.
platelet aggregates to collagen; a platelet plug is formed
Primary Aggregation:
release of adhesive glycoprotein and ADP(induction of aggregation to increase the plug size)
Secondary Aggregation
formation of a blood clot (fibrin) conversion of fibrinogen to fibrin by thrombin
Blood Coagulation:
Plasmin (proteolytic enzyme)
Clot Removal:
what are the transient/free cells
macrophage, plasma cells, leukocytes, mononuclear phagocyte system
what are the fixed cells
Fibroblasts, mast cells, adipose cells, pericytes
Platelets are fragmentations of
Megakaryocytes
Number of nucleus of megakaryocyte
Multinucleated
Component of platelet that is responsible for adhesion
Glycoprotein
Electron dense granules of the granulomere
Delta granules
Larger granules of the granulomere
Alpha granules
Formed elements which maintain the integrity of blood vessels
Platelets
Formed elements which form hemostatic plugs to stop blood loss from injured vessels
Platelets
Formed elements which promote coagulation of plasma factors
Platelets
What is released in secondary aggregation to increase plug size
Adhesive glycoprotein and ADP
What is used to convert fibrinogen to fibrin
Thrombin
A proteolytic enzyme responsible for clot removal
Plasmin
Secretion of plasma cells
Ab secretion
Type of collagen which bind basal lamina to reticular fibers
Type VII
Type of collagen
Major structural component of basal lamina
Type IV
CT with Mineralized ground substance
Bone
CT with gelatinous and syrupy GS
Loose
Dense
Cartilage
Adipose
Ct with watery GS
Blood plasma
Protein fiber that connects cells to matrix
Fibronectin
Protein fiber that forms filaments and sheets
Fibrillin
Protein fiber for stretch and recoil
Elastin
Protein fiber: stiff and flexible
Collagen
Intercellular source of secondary mediators
Membrane lipid
Intercellular source of primary mediators
Granule
Secondary mediator
Vasoconstriction
Prostaglandins D2
Secondary mediator
Vasodilation
Contraction of bronchial smooth muscle cells
Leukotriene C4, D4, E4
Vascular permeability, responsible for pain sensation
Bradykinins
Secondary mediator
causes platelet aggregation
Thromboxane A2
Secondary mediator
Inactivates leukotriene C4
Aryl sulfate
Secondary mediator
Attracts eosinophils and basophils
Vascular permeability
Platelet activating factor
Granules of granulomere
(Electron dense): has ADP, ATP, serotonin
Delta Granules
