Connective Tissue Flashcards

Question

Development of Fat Cells

Answer 1

They come from mesenchymal stem cells which can become fibroblasts or lipoblasts and then the lipoblast can become white or brown fat cells

Answer 2

Adipocyte to Capillaries 1) adipocytes store fat (energy) and this energy is used when we need it to burn fat to produce energy 2) triglyceride will be cleaved, perfused into a capillary, and then picked up. 3) It can also shift back to be stored by the fat cells

Answer 3

o Surround endothelial cells (rounded cell that wraps around) o Have characteristics of endothelial cells and smooth muscle cells: contractile- involved in blood flow; main function is contraction o Plays a role in the blood–brain barrier o Angiogenesis and the survival of endothelial cells o Multipotential: wound healing-gives rise to connective tissue and blood vessels (i.e undifferentiated stem cell-like)

Answer 4

``` • Oval to round • IgE on surface • Filled with metachromatic secretory granules – histamine – heparin – neutral proteases – ECF-A (eosinophil chemotactic factor of anaphylaxis) – NCF (neutrophil chemotactic factor) – leukotrienes – prostaglandins – cytokines ``` * have single nuclei along with course and OBVIOUS granules * found in the loose ct in skin and under the mesentry in intestines * Because it is actively producing proteins, it is common to see a lot of the cellular organelles needed for protein synthesis in the mast cells

Answer 5

- Phagocytic - Antigen presenting - long living - fixed and wandering "Scavenger cells that find and destroy the bad guys"

Answer 6

1) Recognition and Attachment: microbes bind to phagocyte receptors 2) Engulfment: Phagocyte membrane zips up around microbe 3) Kill and Degrade: Killing of microbes by lysosomal enzymes in phagolysosome

Answer 7

- the process by which a pathogen is marked for ingestion and destruction by a phagocyte

Answer 8

Monocyte - found in blood and is a precursor to macrophages Macrophage - found connective tissue, lymphoid organs, lungs, production of cytokines, chemotactic factors, and other imflamatory dense molecules; antigen presentation Kupffer cell - found in liver; same function as macrophages Microglia - found in nervous tissue Langerhans cells - found in skin Osteoclast - found in founds; digestion of bone Multinuclear giant cell - digestion in ct

Answer 9

• Arise from B-lymphocytes • Ovoid, basophilic • Well developed rER • Juxtanuclear golgi • Secretes antibodies***** • clumps of heterochromatin create a "clock face" pattern of nuclear chromatin in which the nucleolus is eccentrically located and surrounded by CH like clock

Answer 10

* Collagen * Reticular * Elastic

Answer 11

type I = dermis, bone, capsules of organs, fibrocartilage, dentin, cementum type II = hyaline and elastic cartilages type III = eticular fibers type IV = basal lamina type V = placenta type VII = anchoring fibrils of the basal lamina (example: anchoring the fibrils produced in epithelium; epidermis is anchored by dermis) *NOTE* When you say "collagen" by default, you are referring to Type I collagen; "collagenous tissue" means having type I collagen

Answer 12

(largest) Collagen fiber bundle>>fibers>>smaller fibrils >> aggregates of tropocollage molecules (smallest) Tropocollagen molecules self-assemble: gap and overlap The gap and overlap: in register with tropocollagen molecules of neighboring rows Hydroxyproline residues of α chains: maintain the stability of the tropocollagen molecule (3 alpha chains) The gaps are actually stained darker compared to the areas of overlap because the gaps hold more dye

Answer 13

* Type III collagen * THINNER and MORE CARBOHYDRATES than type I fiber * stains black with silver stain and is invisible with H&E * produced by reticular cell * produce a scaffolding network (MESH-LIKE and less organized than collagen so it can hold a lot of cells) Common in lymph nodes and spleen (specifically a major constituent of splenic cords in the red pulp)

Answer 14

• Can stretch 150% of length • Fiber composed of – Outer- microfibrils of fibrillin (glycoprotein) – Inner- amorphous core of elastin Stains darker than collagen fibers in H&E staining and also appear much thinner than the collagen bundles Van Gieson staining is also a special staining that allows you to see elastic fibers (stain a dark blue/black color)

Answer 15

Blood vessels have an internal elastic membrane called the tunica intima under the epithelium (simple squamous) Next is the tunica media layer which is layer of smooth muscle containing elastic fibers as well and then the tunica externa is the collagen fibes Need the elasticity for expansion and contraction of theses thick vessels

Answer 16

• Complex of macromolecules • Fills space between fibers and cells – organizes Lssue topography, supports cell migration, orients cells, induces cell behavior – binds growth factors, cytokines-reservoir • Three classes of compounds – Glycosaminoglycans (GAGs) – Proteoglycans – Multiadhesive glycoproteins

Answer 17

* Repeating disacharide: Hexozamine +uronic acid * Hydrophilic polyanions (can bind cations such as sodium) * Part of proteoglycan * Osmotic pressure leads to increased water content- firmness, flexibility * Hyaluronic acid is the most ubiquitous GAG

Answer 18

Glycosaminoglycans are made up of repeated disaccharide units which then come together and attach onto one large core protein The GAGs attached on to a core protein = a PROTEOGLYCAN (has a brush-like appearance)

Answer 19

* Protein component predominates * Globular protein with carbohydrate, attached carbohydrates are usually branched * Cell-cell and cell-substrate 1. Fibronectin: synthetized by fibroblasts and epithelial cells 2. laminin: participate in adhesion of epithelium cells to basal lamina 3. Integrins: Matrix receptor

Answer 20

Exists as a protein dimer, consisting of two nearly identical monomers linked by a pair of disulfide bonds Three binding domains 1) cells 2) collagens 3) GAGs

Answer 21

Trimeric proteins that contain three chains participate in adhesion of epithelium cells to basal lamina Three binding domains 1) cells 2) collagens 3) GAGs

Answer 22

Have two different chains - the α (alpha) and β (beta) subunits Are cell-surface molecule that bind to collagen, fibronecytin and laminin Are transmembrane receptors or linker proteins and interact also with cytoskeleton AcHn microfilaments Plays a role in signaling transduction and can bind to specific ligands and activate down stream cell signaling

Answer 23

BASICALLY, secretory granules will come to the plasma membrane, fuse, and secrete the products out and ilicit an inflammatory response DETAILS BELOW: 1) Binding of antigen to IgE-receptor complex causes cross-linking of IgE and consequent clustering of receptors 2) Activation of adenylate cyclase 3) Activation of protein kinase 4) Phosphorylation of protein 5) Release of Ca2+ 6) Fusion of granules 7_ Release of granules' contents or secretion of leukotrienes, thromboxanes/prostaglandins

Answer 24

Histamine: vasodilation and increased vascular permeability (why we have stuff noses) Eosinophil Chemotactic Factor (ECF) recruits eosinophil to take care of parasitic infections Neutrophil Chemotactic Factor: released in response to bacterial infection (microorganisms) Leukotrienes: increase vascular permeability/enhance effects of histamine Thromboxane A2: platelet-aggregating mediator and VASOCONSTRICTION

Answer 25

o Similar to blood plasma in ions o Similar to blood plasma in diffusible substances o Contains low molecular weight plasma proteins o Circulation to feed cells and remove waste

Answer 26

In a blood vessel, there is an arteriole end and a venule end and two pressures exist between them: hydrostatic and osmotic pressure There is a decrease in hydrostatic pressure and an increase in osmotic pressure from the arterial to the venous ends of blood capillaries Fluid leaves the capillary through its arterial end and re-penetrates (enters) the blood at the venous end while some fluid is also drained by the lymphatic capillaries

Answer 27

when there is a decrease in colloid osmotic pressure, water accumulates in the connective tissue This is because water leaves blood vessel from arterial end is not drawn back into the capillaries at venous ends Low osmotic pressure means that the fluid will stay in the tissue and it will cause swelling (EDEMA)

Answer 28

Basically made of two parts: epidermis ( stratified squamous epithelium) and dermis (dense irregular collagen ct) Skin also has appendages such as sweat and sebaceous glands, hair, hair follicles and nails

Answer 29

1) Cellulitis: infection > Requiring intravenous antibiotics > 80% of cases of cellulitis of the submandibular space caused by dental procedure 2) Scarred CT in dermis > collagen bundles are irregular in the tissue but if they are really curvy and abnormal, it is actually scar tissue 3) Keloid Formation: >Excessively thick layer of the dermis; apparent large, eosinophilic, type I collagen fibers

Answer 30

Non-Inherited CT disorder Vitamin C (ascorbic acid) deficiency leads to scurvy, a disease characterized by the degeneration of connective tissue. Ascorbic acid is a cofactor for proline hydroxylase, which is essential for the normal synthesis of collagen More pronounced in areas in which collagen renewal takes place at a faster rate (periodontal ligament) leads to a loss of teeth.

Answer 31

1) Ehlers-Danlos syndrome (EDS) 2) Marfan syndrome 3) Osteogenesis Imperfecta 4) Epidermolysis bullosa

Answer 32

Actually a group of more than 10 disorders Defect in collagen synthesis (col I or III): - progressive deterioration of collagens Characterized by over-flexible joints, stretchy skin, and abnormal growth of scar tissue. Depending on the specific form of EDS, other symptoms may include: - A curved spine - Weak blood vessels - Bleeding gums - Problems with the lungs, heart valves, or digestion

Answer 33

abnormal fibrillin gene Fibrillin gene is required to make elastic fibers The elastin protein makes the core and then the fibrillin to cover the core protein to make the functional elastic fiber

Answer 34

Autosomal domninant disease: brittle bones Present at birth Defect type I collagen gene or different defects that can affect this gene Has oral manifestions as lack of/weak dentin and cementum because type I collagen also makes these fibers so the teeth are weak and miscolored

Answer 35

Fragile skin: Butterfly children Mutations in the COL7A1 gene: anchoring fibrils Type VII collagen: connect the epidermis to the dermis. When it is abnormal or missing, friction or other minor trauma can cause the two skin layers to separate Causes blistering in response to minor injury, heat, or friction from rubbing, scratching or adhesive tape

Answer 36

Body's normally protective immune system produces antibodies that target the body's own tissues for attack

Answer 37

Excess production of collagen buildup of scar tissue (fibrosis) in the skin and other organs Hard and thick skin, swelling or pain Localized and systemic sclerosis Women are four times more likely to develop Autoimmune Diseases, exact cause is unknown

Answer 38

1) Plasma Cell Gingivitis 2) Irritation Fibroma (traumatic fibroma, focal fibrous hyperplasia) 3) Peripheral Ossifying Fibroma 4) Peripheral Giant Cell Granuloma 5) Desmoplastic fibroma

Answer 39

caused by an allergic rxn which activates the plasma cells in the area

Answer 40

Also traumatic fibroma, focal fibrous hyperplasia most common of all hyperplastic growths in the oral cavity hyperproliferations of collagen due to injury; not true neoplasm

Answer 41

A form of reactive hyperplasia that frequently contains bone the lesion arises from the PDL structures or periosteum

Answer 42

Most often affects the gingival Fibroblasts and endothelial cells: often coalesce into multinucleated giant cell forms May surround sinusoidal spaces.

Answer 43

Benign fibrous infiltrative proliferation: very dense mature collagen mandible of young patients mandibular resection recurrence rate 25%