Connective Tissue Flashcards
Maintain the form of organs throughout the body
Connective tissue
Provide a matrix that supports and physically connects other tissues and cells together in organs
Connective tissue
__________ of connective tissue gives metabolic support to cells as the medium for diffusion of nutrients and waste products
Interstitial fluid
Connective tissue Originate from embryonic
mesenchyme
Major constituent of connective tissue is the
extracellular matrix (ECM)
Fibers
Ground substances
- complex of anionic, hydrophilic proteoglycans, glycosaminoglycans (GAGs), and multi-adhesive glycoproteins (laminin, fibronectin, and others)
Ground substance
(such as collagens and elastic fibers)
Protein fibers
consists of closely aggregated cells connected firmly to one another in the form of cellular sheets that line the interior of hollow organs and cover the body surface
EPITHELIAL TISSUE
composed of epithelial cells and a small amount of extracellular matrix
EPITHELIAL TISSUE
arranged cellular sheets either in single or multiple layers
EPITHELIAL TISSUE
avascular except stria vascularis of the inner ear
EPITHELIAL TISSUE
forms the covering of various organs and thus is the outermost tissue in most organs
EPITHELIAL TISSUE
various organs like skin, buccal cavity, the lining of blood vessels, body cavities, glands, and their
ducts
EPITHELIAL TISSUE
less abundant than connective tissue
EPITHELIAL TISSUE
made up of cells, fibers, and gel-like substances that supports and gives structure to the body
CONNECTIVE TISSUE
composed of different cells and a
larger amount of extracellular matrix
CONNECTIVE TISSUE
scattered throughout the matrix in no particular arrangement
CONNECTIVE TISSUE
vascular except for cartilages
poorly vascular-tendons and ligaments
CONNECTIVE TISSUE
usually present underneath the epithelial tissue
CONNECTIVE TISSUE
forms the bones, cartilages, adipose tissue, reticular tissue, and the blood
CONNECTIVE TISSUE
most abundant animal tissue
CONNECTIVE TISSUE
Elastic fiber
Collagen fiber
Reticular fiber
Protein fibers
Resident cells
Mesenchymal cell
Macrophage
Adipocyte
Fibroblast
Product of fibroblasts
Extracellular fibers and ground substance
Product of Plasma cells
Antibodies
Responsible for Various immune/defense functions
Lymphocytes (several types)
Responsible for: Modulate allergic/vasoactive reactions and defense against parasites
Eosinophilic leukocytes
ANTIPARASITIC!!!!!!
Responsible for Phagocytosis of bacteria
Neutrophilic leukocytes
Responsible for Phagocytosis of ECM components and debris; antigen processing and presentation to immune cells; secretion of growth factors, cytokines, and other agents
Macrophages
Responsible for: Pharmacologically active molecules (eg, histamine)
Mast cells or Basophils
Storage of neutral fats
Adipocytes
Produce and maintain most of the tissue’s extracellular components
Fibroblasts
Synthesize and secrete collagen and elastin, as well as the GAGs, proteoglycans, and glycoproteins
Fibroblasts
______ fibroblast - nucleus is large, ovoid, euchromatic, and has a prominent nucleolus
Active
usually spindle-shaped and contains a darker, more heterochromatic nucleus
Quiescent fibroblast “fibrocyte
Produce and maintain most of the tissue’s extracellular components
Large, mesenchymally derived cells
ADIPOCYTES
Specialized for cytoplasmic storage of lipid as neutral fats, or less commonly for the production of heat.
Adipocytes
Cushion and insulate the skin and other organs
Adipocytes
- phagocytic ability and specialize in turnover of protein fibers and removal of dead cells, tissue debris, or other particulate material
Macrophages
Measures between 10 and 30 μm in diameter and has an eccentrically located, oval or kidney-shaped nucleus.
MACROPHAGES
MACROPHAGES also known as
HISTIOCYTES
Macrophages derive from bone marrow precursor cells that divide, producing______
monocytes
T or F| Monocytes and macrophages are the same cell at different stages of maturation
TRUEEEEEEE
Oval or irregularly shaped connective tissue cells, between 7 and 20 μm in diameter
MAST CELLS
Cytoplasm is filled with basophilic secretory granules
Nucleus is centrally situated
Abundant secretory granules
Mast cells
Roles in the local inflammatory response, innate immunity, and tissue repair.
Mast cells
- sulfated GAG that acts locally as an anticoagulant
Heparin
- promotes increased vascular permeability and smooth muscle contraction
Histamine
- activate various mediators of inflammation
Serine proteases
attracts leukocytes
Eosinophil and neutrophil chemotactic factors
- polypeptides directing activities of leukocytes and other cells of the immune system
Cytokines
- precursors for conversion to prostaglandins, leukotrienes, and other important lipid mediators of the
inflammatory response.
Phospholipid
B-lymphocyte–derived, antibody- producing cells
Large, ovoid cells have basophilic cytoplasm due to their richness in RER
PLASMA CELLS
Nucleus is generally spherical but eccentrically placed
Clock-face appearance
PLASMA CELLS
Wandering cells in connective tissue Leave blood via diapedesis
Increases greatly during inflammation
LEUKOCYTES
Most abundant protein in the human body
Strong and resistant to normal shearing and tearing forces
COLLAGEN
Initiated by specific enzymes called collagenases, which are members of an enzyme class called matrix metalloproteinases (MMPs).
COLLAGEN DEGRADATION
Consist mainly of collagen type III
RETICULAR FIBERS
Characteristically stained black by impregnation with silver salts - termed argyrophilic
RETICULAR FIBERS
Occur in the reticular lamina of basement membranes and surround adipocytes, smooth muscle and nerve fibers, and small blood vessels
RETICULAR FIBERS
Form sparse networks interspersed with collagen bundles in many organs
Have physical properties to be stretched or distended and return to their original shape
Composite of fibrillin microfibrils embedded in a larger mass of cross- linked elastin.
ELASTIC FIBERS
Highly hydrated, transparent, complex mixture of macromolecules, principally of three classes
GROUND SUBSTANCE
GROUND SUBSTANCE
three classes:
glycosaminoglycans (GAGs) proteoglycans multiadhesive glycoproteins
Fills the space between cells and fibers in connective tissue and, because it is viscous:
acts as both a lubricant and a barrier to the penetration of invaders
GROUND SUBSTANCE
GLYCOSAMINOGLYCANS
Also called
mucopolysaccharides
Long polysaccharides consisting of repeating disaccharide units, usually a uronic acid and a hexosamine
GLYCOSAMINOGLYCANS
Largest and most ubiquitous GAG is
hyaluronic acid
Composed of a core protein to which are covalently attached various numbers and combinations of the sulfated GAGs
Synthesized on RER, mature in the Golgi, where the GAG side chains are added
Example: Aggrecan, Decorin, Syndecan
PROTEOGLYCANS
Large molecules with branched oligosaccharide chains and have important roles in the adhesion
Multiple binding sites for cell surface receptors (integrins)
MULTIADHESIVE GLYCOPROTEINS
- provides adhesion for epithelial and other cells, with binding sites for integrins, type IV collagen, and specific proteoglycans
Laminin
As binding sites for collagens and certain GAGs, and forms insoluble fibrillar networks throughout connective tissue
Provides specific binding sites for integrins and is important both for cell adhesion and cellular migration through the ECM
Fibronectin
- act as matrix receptors for specific sequences on laminin, fibronectin, some collagens, and certain other ECM proteins
Cytoplasmic portions of integrins associate with the peripheral membrane proteins talin and vinculin, which together bind actin filaments
Integrin
