Connective Tissues Flashcards
Proteoglycans are different from other glycoproteins because _____.
the GAG chains can be up to 95% of their mass.
________ function in bone resorption and remodeling
Osteoclasts
_____ and _____ derive and differentiate from monocytes.
Macrophages; osteoclasts
There are at least ____ different alpha collagen chains encoded by human genes.
25
_____ appears to help organize the elastin elements in the fiber.
Fibrillin
The ECM controls cell _____, _____, and ______.
proliferation, differentiation, metabolism
The extracellular matrix (ECM) consists of ____, _____, and _____.
structural fibers, glycoproteins, and polysaccharides
The ____ includes the prominent thick epimysium (outer covering) of the muscles.
deep fascia
______ are the pre-eminent cells of most connective tissues in the body.
Fibroblasts
______ are capable of smooth muscle-like function.
Myofibroblasts
The connective tissues near the body surface form a nearly continuous compartment of relatively loose and easily dissected tissue called _____.
superficial fascia
Each collagen molecule is composed of _____ that form a fairly rigid rope-like _____.
three intertwined polypeptide chains; triple helix
Blood and lymph capillaries, as well as nerves, are typically abundant in _____.
loose connective tissue
What are the 3 steps of wound healing?
1) Inflammation and blood clotting 2) New tissue formation 3) Tissue remodeling
Mesenchymal cells are precursors to all of the ______.
connective tissue family members
_____ is an abundant component of fibrillar collagen.
Collagen Type I
Hyaluronic acid is not attached to a _____.
protein core
______ is a hallmark of diseases such as ulcerative colitis or Crohn’s disease (inflammatory bowel diseases), rheumatoid arthritis, stomach ulcers, and several skin disorders.
Chronic inflammation
_____ and _____ are the cells that make bone.
Osteoblasts; osteocytes
_____ are the cells that make cartilage.
Chondrocytes
Chondrocytes are the cells that make _____.
cartilage
Mesenchymal cells primarily function in _____.
embryogenesis
Macrophages and osteoclasts derive and differentiate from ______.
monocytes
The ______ consists of structural fibers, glycoproteins, and polysaccharides.
extracellular matrix (ECM)
Macrophages are large “engulfing” cells that _____.
phagocytose
Cytokines are secreted by ______ and _____.
white blood cell derivatives; fibroblasts
Fibroblasts can differentiate into other connective tissue cell types such as _____, ______, ________, and ______.
1) adipocytes 2) smooth muscle cells 3) chondrocytes 4) osteoprogenitor cells
_____ surround and permeate all of the organs of the body.
Loose and dense connective tissues
_____ are large “engulfing” cells that phagocytose.
Macrophages
______ and ______ are relatively high in loose connective tissues.
Cell densities; ground substance components
_____ contain thick collagen fibrils that are very abundant relative to ground substance, and have a low number of cells.
Dense connective tissues
Adipocytes are derivatives of _____ and/or primitive _____.
fibroblasts; mesenchymal cells
_____ are synthesized on the ER and translocated during synthesis to the ER lumen.
Collagen polypeptides
______ are different from other glycoproteins because the GAG chains can be up to 95% of their mass.
Proteoglycans
The deep fascia includes the prominent thick _____ of the muscles.
epimysium (outer covering)
_____ are found in connective tissues that require a contractile function.
Myofibroblasts
The _____ are clinically important because their levels in urine and blood are used to diagnose important connective tissue and bone disease.
N-telo peptides
_____ is a filamentous protein that exists in a predominantly random coil conformation.
Elastin
These cells are often generated at the site of wounds where their contractile function contributes to retraction and shrinkage of scar tissue.
Myofibroblasts
Lymphocytes are central to _____ to foreign organisms/viruses/materials.
acquired immunity
______ are phagocytic cells that are derived from blood monocytes and are very similar to ______.
Osteoclasts; macrophages
Elastic fibers contain the proteins ____ and _____ that assemble into stretchable and resilient fibers and sheets.
elastin; fibrillin
Mast cells differentiate from _____.
basophils
Macrophages have several important physiological functions, including _____, _____, ______, and ______.
i) phagocytossis (ii) angiogenesis (iii) remodel damaged tissue (iv) remodel normal developing tissue and organs as part of their morphogenesis
Neutrophils and eosinophils are important for ______.
defense against microorganisms
Collagen polypeptides are synthesized on the ____ and translocated during synthesis to the ____.
ER; ER lumen
What are immigrant blood-derived cells?
white blood cells that are produced from hematopoietic cells in the bone marrow and then migrate from blood into connective tissue
_____ differentiate from basophils.
Mast cells
The cells found in connective tissues are of two general categories: _____ and immigrant blood-derived cells.
Core “resident” cells of the CT family
Collagen Type I is an abundant component of _____.
fibrillar collagen
_____ are derivatives of fibroblasts and/or primitive mesenchymal cells.
Adipocytes
Loose and dense connective tissues surround and permeate all of the ____ of the body.
organs
These collagens form very thin fibers and assemble into interlaced networks that form porous sheets.
Network-forming collagen
_____ can differentiate into other connective tissue cell types such as adipocytes, smooth muscle cells, chondrocytes, and osteoprogenitor cells.
Fibroblasts
What allows the ECM to resist large compression forces?
a high swelling (turgor) pressure
Numerous _____ can signal long distance to hematopoietic tissue to stimulate productions of more white blood cells.
cytokines
Collagen Type IV is a common component of the network-forming sheets in _____.
the basal laminae
______ decorate the surfaces of collagen fibrils and are thought to link collagen fibrils.
Fibril-associated collagen
The ECM controls epithelial cell ____.
polarization and shape
Network-forming collagen is found in the ______.
basal laminae
_____ are central to acquired immunity to foreign organisms/viruses/materials.
Lymphocytes
_____ are the most abundant structural fibers of the ECM.
Collagen fibers
Each _____ is composed of three intertwined polypeptide chains that form a fairly rigid rope-like triple helix.
collagen molecule
What is the ground substance?
a hydrated aqueous gelatinous material that holds the fibers
The ______ can be arranged in parallel-organized sheets, such as in ligaments and tendons.
dense CT collagen bundles
Fibril-associated collagen decorate _____ and are thought to ____ collagen fibrils.
the surfaces of collagen fibrils; link
Proteoglycans contain a protein core attached to very large acidic polysaccharides called ______.
glycosaminoglycans (GAGs)
These molecules can function as selective sieves by forming gels of varying pore sizes
GAGs
The ECM controls _____, _____, and _____ of tissue structure.
formation, organization, and modification
Myofibroblasts are capable of _____.
smooth muscle-like function
_____ are the central CT cell type that makes the components of the extracellular matrix of most connective tissues.
Fibroblasts
______ secreted by mast cells is thought to promote endothelial permeabilization.
Histamine
_____ are important in edema and allergic hypersensitivities.
Mast cells
______ is a common component of the network-forming sheets in the basal laminae.
Collagen Type IV
Mast cells are important in _____ and ______.
edema; allergic hypersensitivities
Malignant metastatic tumors are believed to co-opt inflammatory processes to _____.
promote their continued growth and vascularization
Connective tissues (CT) function to provide ____ and _____ for the specialized tissues of organs.
mechanical strength; support
What are mast cells?
secretory cells
_____ are glycosylated and hydroxylated on selected amino acid residues.
Collagen polypeptides
Connective tissues (CT) function to _____ that contact the connective tissue matrix (the ECM).
control the behavior and functions of cells
______ primarily function in embryogenesis.
Mesenchymal cells
Osteoclasts are ______ that are derived from blood ______ and are very similar to macrophages.
phagocytic cells; monocytes
______ is not attached to a protein core.
Hyaluronic acid
Superficial fascia contains _____.
several distinct layers of connective tissue
_____ produce the fibrous proteins, proteoglycans, and other components of the ECM.
Fibroblasts
_____ are secretory cells that, when stimulated by immune responses, release various substances, including vasodilators.
Mast cells
Chronic inflammation is a hallmark of diseases such as _____, ______, ______, and _____.
ulcerative colitis or Crohn’s disease (inflammatory bowel diseases), rheumatoid arthritis, stomach ulcers, and several skin disorders
Cell densities and ground substance components are relatively high in _____.
loose connective tissues
Osteoblasts and osteocytes are the cells that _____.
make bone
The cells found in connective tissues are of two general categories: Core “resident” cells of the CT family and _____.
immigrant blood-derived cells
Connective tissues (CT) function to conduct and control the exchange of _____, _____, and _____.
nutrients; metabolites; signaling ligands
GAGs are long polymers of _____.
carbohydrate molecules (polysaccharides)
Fibroblasts are the pre-eminent cells of _____.
most connective tissues in the body
_____ are found where tissues must resist strong shear forces in particular directions.
Dense CT collagen bundles
_____ aggregate to form fibers of varying sizes and organizations.
Collagen proteins
_____ are precursors to all of the connective tissue family members
Mesenchymal cells
Name the 3 components of the ECM.
1) Structural fibers 2) ground substance 3) other extracellular macromolecules
What are immigrant blood-derived cells important for?
defense against infection by viruses and microrganisms, tissue damage, and allergic hypersensitivities
_____ contain a protein core attached to very large acidic polysaccharides called glycosaminoglycans (GAGs).
Proteoglycans
Fibroblasts produce _____, _____, and other components of the ECM.
the fibrous proteins, proteoglycans
Name the 7 core “resident” cells of the CT family.
1) Mesenchymal cells 2) Fibroblasts 3) Myofibroblasts 4) Adipocytes 5) Osteoblasts 6) Chondrocytes 7) Some smooth muscle cells
The ______ of collagen are cleaved by specific proteases.
N- and C-termini
The ECM provides a defense against _____.
infectious agents
Macrophages are also critical regulatory cells that _____ and _____ numerous extracellular signals.
secrete; respond to
Collagen is synthesized and modified ______ and then secreted and further modified _____.
intracellularly; extracellularly
Macrophage-produced signals have numerous functions that include _____, ______, ______, and ______.
1) angiogenesis 2) immune cell migration and function 3) fibroblast activation 4) blood vessel permeability
Name the 5 immigrant blood-derived cells.
1) Lymphocytes 2) Macrophages 3) Neutrophils and eosinophils 4) Mast cells 5) Osteoclasts
______ produce the extracellular matrix (ECM).
Connective tissues
_____ are long polymers of carbohydrate molecules (polysaccharides).
GAGs
Myofibroblasts are derived from ______.
fibroblasts
The N-telo peptides are clinically important because their levels in urine and blood are used to _____.
diagnose important connective tissue and bone disease
Connective tissues (CT) function to control the behavior and functions of cells that _____.
contact the connective tissue matrix (the ECM)
There are at least 25 different _____ encoded by human genes.
alpha collagen chains
______ are also critical regulatory cells that secrete and respond to numerous extracellular signals.
Macrophages
Collagens are post-translationally modified (_____ and ______ on selected amino acid residues)
glycosylated; hydroxylated
The dense CT collagen bundles can be arranged in _____, such as in _____ and ______.
parallel-organized sheets; ligaments; tendons
These are white blood cells that are produced from hematopoietic cells in the bone marrow and then migrate from blood into connective tissue
immigrant blood-derived cells
_____ are derived from fibroblasts.
Myofibroblasts
Osteoclasts function in _____ and _______.
bone resorption; remodeling
_____ are secreted by white blood cell derivatives and fibroblasts.
Cytokines
Dense connective tissues contain ______ that are very abundant relative to ground substance, and have a low number of _____.
thick collagen fibrils; cells
What is a fibril?
a large bundle of collagen molecules
Fibroblasts are the central CT cell type that makes the components of the _____ of most connective tissues.
extracellular matrix
Histamine secreted by ______ is thought to promote ______.
mast cells; endothelial permeabilization
The ECM guides and regulates _____.
cell migration through the matrix
Name 3 properties of GAGs are relevant to their function.
1) highly negatively charged 2) Their rigid extended structure causes them to readily form gels 3) Some proteoglycans can also bind to and inactivate or activate other proteins
____ controls epithelial cell polarization and shape.
The ECM
______ and ______ are important for defense against microorganisms.
Neutrophils; eosinophils
What is the significance of the negative charge on GAGs?
they are very hydrophilic (attract lots of water)
Connective tissues produce the _____.
extracellular matrix (ECM)
______ contain thin collagen fibrils that are relatively sparse and are arranged in irregular lattices.
Loose connective tissues
The ECM controls ____ and _____ due to injury.
inflammation; repair
Loose connective tissues contain _____ that are relatively sparse and are arranged in _____.
thin collagen fibrils; irregular lattices
