CONNECTIVE TISSUE Flashcards
Two general components of matrix
Protein fibres, ground substance
T or F: connective tissue is very cellular
False; epithelia is very cellular
Ct cells produce
matrix : protein fibres, ground substance
characteristics of ___ determine properties of CT
matrix
what force can collagen withstand
tensile
what does 1 collagen trimer consist of
2 alpha 1 chains, 1 alpha 2 chain
name the 5 forms that collagen exists in during synthesis
preprocollagen, pro collagen, collagen, fibrils, fibres
what form of collagen is synthesized by RER
preprocollagen
what is the name of the triple helix of collagen
procollagen
function of registration peptides
maintain solubility of procollagen
which form of collagen has registration peptides
pro collagen (like bodyguards on a “pro”)
what happens to collagen in golgi
post-translational modification; soluble pro collagen packaged in vesicles -> cell surface -> exocytosis
where are pro collagen peptidases located
membrane-bound
how does pro collagen change when registration peptides cleaved
becomes insoluble collagen
what is collagen called when it aggregated extracellularly
fibrils
how are collagen fibrils attached
covalent cross-links
which type of collagen is most common and where is it found
collagen type I; tendons, ligaments, bone
which type of collagen does not form fibres, but remains as fibrils
collagen type 2
which collagen type = reticular fibres
type 3
which type of collagen does not get its registration peptides cleaved and what is the consequence
type 4; non-fibrillar; makes mesh-like sheet for basement membrane
which type of collagen anchors BM to underlying CT
type 7; anchoring fibrils
what is the function of reticular fibres
stroma (scaffolding) fr highly cellular organs
how many times their resting length can elastic fibres stretch to
1.5x
describe the composition of an elastic fibre
elastin fibres surrounded by fibrillar fibres
how are elastic fibres connected
crosslinks
where might elastin be found in sheets, not fibres
aorta; arteries around heart
function of elastic fibres
resiliency; stretch and recoil
3 functions of ground substance
adhesion for cells, fibres; resists compression; medium for molecular diffusion between plasma and ICF
2 components of GS
tissue fluid + organic molecules
2 types of organic molecules in GS
proteoglycans, adhesive glycoproteins
name the 2 types of forces experienced by fluid in blood vessels
hydrostatic force (pushing out) and oncotic/osmotic force (pulling in)
what causes oncotic pressure
plasma proteins, mainly albumin (too big to exit BVs)
3 compartments of ECF
interstitial, intravascular, transcellular
how to determine movement of fluid across BV wall
vector sum of 2 pressures; hydrostatic and oncotic
what is another word for hydrostatic pressure
blood pressure
when BP > PO
fluid extravasated
when BP < PO
fluid moves into BV
which vessel has lowest hydrostatic P
lymphatic
is BP higher on arterial or venous side?
arterial; fluid leaves
venous side: BP __ OP
BP < OP; fluid into vessel
what is detected in lymph nodes
antigen, cancerous cells
function of lymph node
in line filter for lymph; limit spread of disease, infection
diameter of lymph node
2-10 mm
_fferent lymph is filtered
Afferent
where are lymph nodes numerous
axillae, groin, neck, mesenteries, mediastinum (thorax)
T or F: all lymph passes through 4 lymph nodes before venous
F; at least 1
why do lymph nodes become enlarged with infection
B cells proliferate
what 2 veins does lymph drain into
internal jugular vein; subclavian vein
what is the name of the vein where internal jugular and subclavian unite
brachiocephalic vein
what is edema
excess tissue fluid
2 general causes of edema
increased production of tissue fluid
(more vascular permeability, less oncotic pressure)
or
decreased clearance (raised venous pressure (pregnancy), lymphatic obstruction (raises lymphatic pressure))
T or F: GAGs are flexible
F; inflexible like bristles of steel brush
GAGs are composed of repeating _______ units
disaccharide (unbranched)
why do GAGs make GS slippery & viscous
high negative charge => very hydrophilic
2 components of proteoglycan structure
GAGs + core protein
which molecule type makes GS slippery
proteoglycans
why can GS resist compression
proteoglycans; their GAGs hold water
what slows diffusion of molecules through interstitial fluid
proteoglycans (filter)
describe the composition of adhesive glycoproteins
proteins with carbohydrates bound
binding sites for what on adhesive glycoproteins
protein fibres, GAGs, integrins (cell membrane)
fibronectin, osteonectin, achondronectin, and laminin are all types of ____
adhesive glycoproteins
what stabilizes the ECM by linking its components to the cell surface
adhesive glycoproteins
T or F: basement membrane is acellular
T
what other types of cells does BM surround
smooth muscle, adipose, schwann
what types of collagen in BM
4 (mesh, non-fibrillar) and 7 (anchoring)
proteoglycan of basement membrane
heparan sulfate
adhesive glycoprotein of basement membrane
laminin
which tissue produces the BM components
both epithelia and CT
4 functions of BM
cell anchorage/support, filtration, scaffold for epithelial repair, binding smooth muscle cells together
embryonic origin of all CT cells
mesenchyme
what epithelial cells also derived from mesenchyme
endothelial, mesothelial
what components of CT do fibroblasts secrete
proteoglycans, adhesive glycoproteins, collagen, elastic fibres
embryonic origin of blood cells
mesenchyme
nucleus of active fibroblast is __
pale (like exhausted)
what cells have signet ring (thin cytoplasm, flat nucleus)
adipose; lipid droplet pushes everything to side
adipose tissue
tissue dominated by adipocytes
what cells have juxtanuclear halo and why
plasma cells; Golgi => pale
5 types of fixed cells
fibroblasts, macrophages, adipocytes, mast cells, mesenchymal stem cells
wandering cells
monocytes, lymphocytes, microphages (neutrophils, eosinophils)
2 cell types called “microphages”
neutrophils, eosinophils
what cell are platelets derived from
megakaryocyte
fxn of mast cells
storage chemical mediators of inflammation, hypersensitivity reactions
how are mast cells activated and what is the result
trauma, antigen ; release of granules
how are mast cells sensitized
antibodies against antigen bind receptors on mast cells’ surface; degranulation if antigen binds the antibody
what kind of receptors on mast cell membrane
Fc
what 3 factors are released by mast cells
histamine (vasodilation, increased vascular permeability); neutrophil chemotactic factor, eosinophil chemotactic factor
macrophages: \_\_\_\_ ; liver \_\_\_\_; CNS \_\_\_\_\_; skin \_\_\_\_\_; bone
Kupffer; microglial; Langerhans; osteoclasts
what makes macrophages get larger
phagocytosis
which cells can leave the blood to function in CT
WBCs/leukocytes (neutrophil, eosinophil, basophil)
2 types of specialized CT proper
reticular; adipose
2 types of supporting CT
cartilage; bone
what CT in mesentery
loose areolar CT
least specialized CT
loose areolar CT (many different components)
main collagen of dense R CT
collagen I
how many directions of tensile strength in dense R CT
1
what CT makes up aponeuroses
dense R CT; sheet (not cord) that attaches muscle
relative amount of GS, cells, cell types in dense regular CT
few
type of collagen in dense irregular CT
collagen type 1
how many directions of tensile force can dense irregular collagen withstand
many
example of dense irregular Ct
dermis ; reticular layer
relative amount of Gs, cells, cell types in dense irregular CT
few
what tissue type in perichondrium
dense irregular CT
T or F: elastic fibres are in both loose areolar CT and dense CT
T
without fibrillin, what does elastin form?
fenestrated sheets; lamellae
what cells produce elastin in the aorta
smooth muscle cells
what is the term for the elastin in the aorta and other blood vessels
lamellae
example of dense CT with elastin
ligamenta flava; elastic ligaments (vertebral column)
T or F: smooth muscle and bone marrow have reticular fibres
T
what forms stroma in adipose tissue
reticular fibres (type 3 collagen)
what tissue acts as the “styrofoam packing chips of the body”
adipose
what is stored in a single lipid droplet in adipose
triglycerides
3 functions of adipose
energy, thermal insulator, shock absorber
name 2 organs that are surrounded by adipose
eyes, kidney
T or F: adipose is not highly vascular
f; adipose is highly vascular
