CONNECTIVE TISSUE CHARACTERISTICS: *Most abundant tissue type; Composed of ECM (GS & Protein Fibers) + Cells (Refer to pp.129-131 for specific characteristics of each) *Highly equipped with VAN assists in diffusion of nutrient and waste to and from epithelium (**Be familiar with exceptions**) *General FXN: p. 128 CLASSIFICATION: I. Embryologic CT (2) A. **Mesenchyme** CT Stem Cell B. Mucous (Umbilical Cord) II. Mature CT A. Loose CT (3) D. Bone ( Osseous/ Osteo- ) (2) 1. Areolar 1. Compact 2. Adipose 2. Spongy 3. Reticular E. Liquid CT (2) B. Dense CT (3) 1. Blood 1. DRCT 2. Lymph 2. DICT 3. Elastic C. Cartilage ( Chondro- ) (3) 1. Hyaline 2. Fibrocartilage 3. Elastic 1
LOOSE CT (3) 1A. AREOLAR CT : consists of all fibers, all cells, semifluid ground substance aka: packing material ; more GS than fibers & cells FXN: strength, elasticity, & support RBCs in capillaries: **d/t epithelium is AVASCULAR** 2 Ground Substance Collagen Fibers Macrophage Cells Fibroblast: Flat cells w/ branching processes
LOOSE CT 1B. AREOLAR CT : consists of all fibers, all cells, semifluid ground substance aka: packing material ; more GS than fibers & cells FXN: strength, elasticity, & support Reticular fiber Plasma cell Fibroblasts Mast cell releasing histamine Collagen fiber
LOOSE CT 2. ADIPOSE CT : Adipocytes (derived from fibroblasts); filled w/ triglyceride droplet w/ nucleus push to periphery; *highly vascular* (significance??); BAT (fxn?) LOC: Sub Q to skin, around heart & kidneys, yellow bone marrow, around joints, and posterior to eyeballs FXN: reduce heat loss, energy reserve, support & protection Nucleus Triglyceride 4
LOOSE CT 3. RETICULAR CT : network branched reticular fibers and cells LOC: Liver, spleen, lymph nodes; RBM; reticular lamina & basement membrane; around blood vessels & muscles FXN: support, binds; provides framework = stroma; & filters 5
DENSE CT (3) 1. DRCT : composed of mainly collagen fibers in an orderly pattern or paralleled (non-living significance???) with many fibroblasts present. LOC: Tendons (muscle-bone), ligaments (bone-bone), aponeuroses FXN: strong attachment; withstands tensile strength along one axis Chains of flat fibroblasts 6
DENSE CT 2. DICT :composed of mainly collagen fibers in irregular arrangement (non-living significance???) with few fibroblasts LOC: fascia, reticular layer of dermis, pericardium, periosteum, perichondrium, joint capsule, organ capsules (find examples), heart valves FXN: provides tensile strength in many directions 7
DENSE CT 3. ELASTIC CT: composed of mainly elastic fibers with fibroblasts LOC: lung tissue, walls of elastic arteries (ex: AORTA), bronchiole tubes, suspensory ligaments of penis, and some ligaments between vertebrae. FXN: stretch & recoil to original shape Elastic fibers Fibroblasts Refer to the Vascular System, Slide #12 on the JayDoc website. Familiarize yourself for class discussion. 8
CARTILAGE CT (3) 1. HYALINE: gelatinous GS, stains vibrant pink or purple, has perichondrium (*except articular surfaces & epiphyseal growth plate* significance??); weakest LOC: most abundant cartilage in body; ends of long bonds (synovial joints), costal cartilage, nose, larynx, and fetal skeleton FXN: provides smooth surfaces for movement, flexibility, & support STRXR: Lacuna, chondrocytes, ECM perichondrium ECM Lacuna w/ chondrocyte note darkly stained nucleus 9
CARTILAGE CT (3) 2. FIBROCARTILAGE: feather-like appearance; NO perichondrium; strongest LOC: IVD, meniscus, pubic symphysis FXN: support & joining structures together; strength & regidity Nucleus of chondrocytes Lacuna not as apparent 10
CARTILAGE CT (3) 3. ELASTIC CARTILAGE: Thread like network of elastic fibers (stains black & grainy), has perichondrium, corn on the cob LOC: epiglottic, external ear (auricle), Eustachian tubes FXN: strength & elasticity; able to maintain shape STRXR: Lacuna, chondrocytes, ECM, elastic fibers perichondrium Lacuna w/ chondrocyte note darkly stained nucleus Elastic fibers 11
OSSEUS BONE CT (2) 1. COMPACT: Thread like network of elastic fibers (stains black & grainy), has perichondrium, corn on the cob LOC: refer to chapter 6 FXN: support, protection ID STRXR: Osteon (Haversian system), Central canal (Haversian canal), lamella, lacuna, osteocytes, canaliculi, Volkmann s canal, & periosteum 2. SPONGY: know difference structures, function, and location, specific to each type of bone (p. 138-139) and chapter 6 12
LIQUID CT (2) 1. BLOOD: Consists of blood plasma & formed elements (RBCs, WBCs, & Platelets) LOC: within arteries & veins, chambers of the heart FXN: RBCs- O 2 & CO 2 ; WBCs immunity, phagocytosis, allergic rxn; platelets - clotting (refer to p. 140 for other terms a& identification characteristics) Refer to slides on JayDoc website: Blood Smear slide #17 & 20 13