Flashcards

Histology Connective Tissue

Marissa Alvarez Histology Graduate English 32 cards

Cards in this deck (32)

1Connective Tissues
2Forms of Connective Tissue Connective tissue proper1. Loose – irregular
2. Dense – regular or irregular
3Forms of Connective Tissue Special connective tissuesAdipose tissue
Elastic tissue
Blood
Mucous tissue
4Forms of Connective Tissue Supporting (skeletal) connective tissuesCartilage
Bone
5Functions of Connective Tissueexchange of metabolites and waste products
electrolyte balance
storage of energy reserves
mechanical support
shock absorption
insulation
source of heat
defense against pathogens
repair after injury
6Distinctive features of connective tissuesConsist of cells and extracellular matrix (ECM)
**The ECM contains fibers and GROUND substance
Cells density is LOW
Blood vessels, lymphatics, and nerves are present
7Connective Tissue: Loose irregular (areolar) CT (Resident cells & Fibers)Resident cells:
Fibroblasts
Fat cells
Macrophages
Mast cells
Plasma cells
Fibers:
Collagen
Reticular
Elastic
Ground substance
8Loose irregular CT Resident Cell: Fibroblasts- synthesize extracellular matrix materials:
precursors for collagen and elastic fibers
components of ground substance
- important in development and wound healing
(from the CT itself)
9Ground Substance
10Loose irregular (areolar) CT Fibers 1. COLLAGENMain fiber type and MOST abundant protein in human body
Synthesized and secreted as a precursor (tropocollagen) by fibroblasts
Assembled into mature fibers spontaneously in the extracellular space.
These fibers have greater tensile STRENGTH per unit weight than steel
At least 27 types exist, of these the most important are:
Type I
Type II
Type III
Type IV
Mutations of the genes coding for collagen lead to serious inherited diseases – e.g., Ehlers-Danlos syndromes (hyper-elastic skin)
11DENSE irregular connective tissue
12Type I Collagen:most common (in internal organs, skin, fascias, tendons, ligaments, bone)
13Type II Collagencartilage (main component of hyaline and elastic cartilage)
in hyalin cartilage
(see images later on in slide set!)
14Type III Collagenreticular fibers
They can only be demonstrated by special stains such as silver impregnation
Reticular fiber network from adrenal cortex, silver stain.
Nuclei are also black, cytoplasm is unstained.
15Type IV Collagenin basement membranes (does not form fibrils)
16Fibers: Elastincan form fibers or fenestrated membranes.
"loose rubber band"
Different protein altogether (NOT collagen)
17Dense REGULAR connective tissue: TENDON (made by fibroblasts + collagen + ground substance) *very straight, matrix of proteins
18Defense cells in connective tissue Resident, intrinsic, or fixed cells:Macrophages (from blood monocytes)
Mast cells (functionally analogous but not identical to basophils in blood)
Plasma cells (from B lymphocytes)
19Defense cells in connective tissue Migrating or wandering cellsAll leukocytes circulating in blood enter connective tissues:
Lymphocytes
Monocytes
Granulocytes
Neutrophils
Basophils
Eosinophils
20After tissue injury, macrophages in regional lymph node engulf erythrocytes (RBC's) MACROPHAGES *main function = Phagocytose (resident cell)
21MAST Cells Main function: release histamine via granules (resident cell)-mediates immune response "trigger"
-Metachromasia: acidity of granules change Toluidine blue dye to a reddish color
22Plasma Cells Main function: antibody production (differentiated B cells) Resident cells (clock-face nucleus and clearing indicating Golgi)
23Fat cells (Adipose Tissue) 2 Types: 1. Unilocular (yellow/white fat) 2. Multilocular (brown fat)
24Fat cells (Adipose Tissue) 1. Unilocular (yellow/white fat)
25Fat cells (Adipose Tissue) 2. Multilocular (brown fat) HEAT generation
26CARTILAGE Type II Collagen -Two types: Elastic & Hyalin Cartilagestructural support
shock absorption
reduce friction in joints
template for bone formation (endochondral ossification)
27Hyaline Cartilage (in the NOSE) Type II Cartilage -surrounded by chondroblasts, then there are perichondrial fibroblasts around the chondroblasts
28Perichondrium and Cartilage Matrix
29Joint Space / Articular Cartilage (empty space = synovial fluid) **LACKS perichondria fibroblasts & chondroblasts (Cannot regenerate - painful: because underlying bone!)
30Elastic Cartilage (Epiglottis, part of the ear) -basically hyalin cartilage BUT has a fibrous look, a form of elastic fibers
31Fibrocartilage **Contains both Types Collagen I and II (cells lined up in rows - pattern present)Pubic symphysis
Meniscus of joints
Part of intervertebral joint
TMJ
*Will replace severely torn
Hyalin Cartilage*
(forms in regions of injury/degeneration within hyalin cartilage)
32EXAM Question: Hyaline Cartilage is composed of: A. Elastic Fibers B. Collagen I C. Collagen II D. Adipose CellsC. Collagen II