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19 Cards in this Set
- Front
- Back
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What is a histamine?
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A chemical mediator that causes contraction of smooth muscles and vasodilation (increasing vascular permeability).
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What is the function of fibroblasts?
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Most abundant cells in CT with oval nucleus responsible for synthesis of ECM components.
Derived from undifferentiated mesenchymal cells. |
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What is the function of macrophages?
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Macrophages are derived from monocytes.
Macrophages are responsible for phagocytosis of foreign substances that enter CT. |
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What is the function of mast cells?
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Mast cells are chemical mediators of the inflammatory response.
They are characterized by their many basophilic secretory granules that release histamines (which increase vascular permeability) in the presence of an antigen. |
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What is the function of plasma cells?
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Plasma cells are large ovoid cells with condensed heterochromatin resembling the face of a clock (bubble in a bubble).
They are responsible for the synthesis and secretion of immunoglobulins (antibodies). |
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What is the function of adipose cells?
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Stems from undifferentiated mesenchymal cells.
Responsible for storage of TG (energy source). |
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What is the function of white blood cells?
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Transient in connective tissue and accumulates in inflammatory responses.
Responsible to protect the body against foreign bodies. 5 types of WBCs. |
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What are the different leukocytes and what do they look like?
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(1) Neutrophilic granulocyte - cell full of granules and has three kidney shaped objects linked to one another.
(2) Eosinophilic granulocyte - same as neutrophilic granulocyte except it has only two kidney shaped objects linked to one another. (3) Basophilic granulocyte - cell full of granules and with a large, irregularly shaped, and multi-lobed nucleus. (4) Lymphocyte - cell without any granules but with a single large nucleus. (5) Monocyte - anything that doesn't resemble the other leukocytes. Has no granules and only one kidney shaped nucleus. B-E-N (123) |
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What forms the extracellular matrix?
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Produced locally by fibroblasts.
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What is the most abundant type of fiber in the ECM? What does it do?
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Collagen fiber. It is a triple-stranded helical rod that provides tensile strength.
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Describe elastic fibers.
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(1) Primarily elastin,
(2) Highly hydrophobic protein, (3) Like Collagen, they are unusually rich in proline and glycine, (4) Unlike Collagen, they are unglycosylated and contain little hydroxyproline protein, (5) Very elastic and (thus) found in distensible organs (lung, blood vessels) --> 5x more extensible than rubber bands |
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What is the relevance of type IV collagen?
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Type IV collagen is a very important constituent of basal laminae.
It forms a mesh-like structure rather than fibrils/fibers (stronger formation). |
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What is the "ground substance" of the ECM?
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It is a viscous, highly hydrated, colorless, transparent, and complex mixture of glycoproteins and proteoglycans involved in binding cells to fibers of connective tissues.
It resists compressive forces and its aqueous phase permits rapid diffusion of nutrients, hormones and metabolites b/t the blood and tissue cells. |
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What are the ECM glycoproteins and purpose do they serve?
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ECM glycoproteins are (1) glycosaminoglycans and (2) proteoglycans.
They function as links b/t cells and ECM constituents (for adhesion and migration). |
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How does fluid move through connective tissue?
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Hydrostatic pressure drives fluid “out” whereas osmotic pressure draws fluid “in”.
Hydrostatic and osmotic pressures are roughly equal in the capillaries. The hydrostatic pressure drives fluid out into the tissue and the resulting solute concentration draws fluid in (osmotic pressure). |
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How does Edema occur?
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Edema occurs when fluid movement is blocked and the fluid accumulates.
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What are the general categories of CT? Describe them.
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Loose CT - not very resistant to stress; flexible and very well vacularized (has many cells, fewer fibers, more ground substance and vascularization that result in delicate consistency and flexibility).
Dense CT - resistant to stress; full of of collagen fibers in bundles that can be regular or irregular in arrangement (regular – tendons, ligaments). |
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What are the functions of connective tissue?
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(1) Defense - physical barrier, impedes movement of bacteria and foreign materials into tissues and contains phagocytic and antibody-producing cells, cells involved in inflammatory responses (can be overcome if microbes produce enzyme that breakdown ECM)
(2) Nutrition and Storage - contains blood vessels and mediates the exchange of nutrients, metabolites, and waste products between tissues and the circulatory system and stores fat deposits and mineral deposits. (3) Repair and Regenerate - fibroblasts capable of replacing ECM components and serve as reservoir of undifferentiated cells from which new connective tissue can arise. (4) Support - packing and shaping of organs, elasticity, mechanical support. DNS-RRS |
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Give an example of a collagen disease.
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Scurvy
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