Lecture 3- Supporting Connective Tissue Flashcards
Supporting Connective tissue types?
- Cartilage
- Osseus tissue (bone)
Tissues
Collections of specialized cells and cell products that perform a relatively limited number of functions.
Primary tissue types
- epithelial
- connective
- muscle
- neural
Matrix
-is a firm gel containing CHONDRIN
Chondrocyte
-Found in small chambers called lacunae
Hyaline Cartilage
- Function: provides stuff but somewhat flexible support; reduces friction between bony surfaces.
- Locations: Between tips of ribs and bones of sternum; covering bone surfaces at synovial joints; supporting larynx (voice box), trachea, and bronchi; forming part of nasal septum.
- Has translucent matrix and the absence of prominent FIBERS.
Elastic Cartilage
- Locations: Auricle of external ear; epiglottis; auditory canal; cuneiform Cartilages of larynx.
- Functions: Provides support, but tolerates distortion without damage and returns to original shape.
- Note: Closely packed elastic fibers are visible between the chondrocytes.
Fibrous Cartilage
- Locations: Pads within knew joint; between pubic bones of pelvis; intervertebral discs.
- Functions: Resists compression; prevents bone-to-bone contact, limits relative movement.
- Note: Collagen fibers are extremely dense, and the chondrocytes are relatively far apart.
Comparison of Cartilage and Bone
-Both support and protect
-Mature cells are located in lacunae in both tissues
-Cartilage is Avascular; bone is highly vascular
-Ground substance in Cartilage is firm but flexible; bone is dense and hard ( but a little flexible)
-Cartilage cannot grow/repair easily; extensive remodeling and repair in bone
•You replace your entire skeleton every 7 years or so
4 types of bone cells
- Osteocyte = maintains bone tissue
- Osteoblasts = forms bone matrix
- Osteogenic cell = stem cell
- Osteoclast = resorbs bone
Two types of osseous tissue
-Compact bone (Dense bone)
•Compact bones are dense and solid.
•Forms the walls of bone outlining the medullary cavity
•Medullary cavity consists of bone marrow
-Spongy bone (Trabecular bone)
•Open network of plates
Epithelial tissue
- Sheet of cells that covers an exposed surface or lines an internal cavity or passage way
- Produces glandular secretions
•Ex: skin
Epithelial Functions
- Provides physical protection
- Control permeability
- Provide sensation
- Produce specialized secretions
Connective tissue
- Fills internal spaces
- Provides structural support
- Stores energy
Muscle tissue
-Contracts to produce active movement
Neural tissue
- Conducts electrical impulses
- Carries information
Simple Squamous Epithelium
- Locations: Mesothelia lining, endothelia lining heart and blood vessels, portions of kidney tubules, inner lining of cornea, alveoli of lungs
- Functions: Reduces friction, controls vessel permeability, performs absorption and secretion
Stratified squamous epithelium
- Locations: Surface of skin, lining of oral cavity, throat, esophagus, rectum, anus, and vagina
- Functions: Provides physical protection against abrasion, pathogens, and chemical attack
Simple Cuboidal Epithelial
- Locations: Glands, Ducts, portions of kidney tubules, thyroid gland
- Functions: Limited protection, secretion, absorption
Stratified Cuboidal Epithelium
- Locations: Lining of some ducts (Rare)
- Functions: Protection, secretion, absorption
Simple Columnar Epithelium
- Locations: Lining of stomach, intestine, gallbladder, uterine tubes, and collecting ducts of kidneys
- Functions: Protection, secretion, absorption
Stratified Columnar Epithelium
- Locations: Small areas of the pharynx, epiglottis, anus, mammary gland, salivarygland ducts, and urethra
- Functions: Protection
Pseudostratified Ciliated Columnar Epithelium
- Locations: Lining of nasal cavity, trachea, and bronchi, portions of male reproductive tract
- Functions: Protection, secretion
Transitional Epithelium
- Locations: Urinary bladder, renal Pelvis, Ureters
- Functions: Permits expansion and recoil after stretching
Merocrine secretion
- Ex: Serous cells of the salvary glands (saliva or mucins from goblet cells in the intestine)
- most common secretion
Apocrine secretion
-Ex: lactiferous cells of the mammary glands
Holocrine secretion
-Ex: Sebaceous gland cells (found by the hair follicle)
Mesenchymal cells (fixed cells)
- Aka stem cells are present in many connective tissues
- Responds to local injury or infection by dividing to produce daughter cells that differentiate into fibroblasts, macrophages, or other connective tissue cells.
Fibroblasts (fixed cells)
- One of the two most abundant fixed cells, always present.
- These stellate (star shaped) cells are responsible for the production of all connective tissue fibers
- Manufactures and secretes protein subunits that interact to form large extracellular fibers.
Fibrocytes (fixed cells)
- Second most abundant Fixed cell in connective tissue proper
- they release chemicals that activate the immune system and attract large numbers of wandering cells involved in the body’s defense mechanisms.
Adipocytes (fixed cells)
-(fat cells)single lipid droplet that occupies almost the entire cell.
Melanocytes
- synthesize and store a brown pigment, melanin that gives tissue a dark color.
- Found in dermis
Connective tissues
-Connective Tissue Proper
•Loose: Fibers create loose, open framework
*Areolar tissue
*Adipose tissue
*Reticular tissue
-Fluid Connective Tissue
•Blood: contained in cardiovascular system
•Lymph: contained in lymphatic system
-Supporting Connective Tissue
•Cartilage: Solid, rubbery matrix
*Hyaline
*Elastic
*Fibrous
•Bone: Bone, crystalline matrixWandering cells
- Free Macrophages
- Mast cells
- Lymphocytes
- Plasmocytes
- Neutrophils
- Easinophils
Free Macrophages
- When circulating within the blood, these cells are called monocytes.
- Reinforces the fixed Macrophages with the frontline defense
Mast cells
-The Cytoplasm of a mast cell is filled with secretory granules of histamine and heparin. These chemicals, which are released after injury or infection, stimulate local inflammation.
Lymphocytes
- Numbers increase markedly wherever Tissue damage occurs
- Can develop into plasmocytes, which are responsible for the production of antibodies, proteins involved in defending the body against disease.
Neutrophils and Eosinophils
- Migrate through connective tissues in small numbers
- When an infection or injury occurs, chemicals released by Macrophages and mast cells attract neutrophils and easinophils in large numbers.
Connective tissue fibers
- Collagen fibers
- Reticular Fibers
- Elastic Fibers
Collagen fibers
- The strongest and most common fibers in connective tissue proper
- Tendons consist almost entirely of collagen fibers
Reticular Fibers
- thinner than collagen fibers, and they form a branching, interwoven framework that is tough but flexible
- abundant in organs such as spleen and liver, where they create a complex 3 dimensional network, or stroma, that supports the parenchyma or distinctive functional cells
Elastic fibers
- Contain the protein ELASTIN
- They are branching and wavy
- after stretching up to 150 percent of their resting length , they recoil to their original dimensions.
Ground substance
- Clear, colors, and similar consistency to maple syrup
- Surrounds cellular and fibrous components of connective tissue
Loose connective tissues
- “packing material “ of the body
- Fill spaces between organs, provide cushioning, and support epithelia
- Also surround and support blood vessels and nerves, store lipids, and provide a route for the diffusion of materials
Types of Loose Connective Tissues
- Areolar Tissue
- Adipose Tissue
- Reticular Tissue
Areolar Connective Tissue
—Locations: within and deep to the dermis of skin, and covered by the epithelial lining of the digestive, respiratory, and urinary tracts; between muscles; around blood vessels, nerves, and around joints
- Functions: Cushions organs; provides support but permits independent movement; phagocytic cells provide defense against pathogens
- all the cells of connective tissue proper are found in Areolar
Adipose Tissue
- Locations: Deep to the skin, especially at sides, buttocks, breasts; padding around eyes and kidneys
- Functions: Provides padding and cushions shocks; insulates (reduces heat loss); stored energy
White: adults
Brown: kids
Reticular Connective Tissue
- Locations: Liver; kidney; spleen; lymph nodes; bone marrow.
- Functions: Provides supporting framework
Types of Dense Connective Tissue
- Dense regular connective tissue
- Dense Irregular connective tissue
Dense Regular Connective Tissue
- Locations: between skeletal muscles and skeleton (tendons and aponeuroses); between bones or stabilizing positions of internal organs (ligaments); covering skeletal muscles; deep fasciae
- Functions: Provides firm attachment; conducts pull of muscles ; reduces friction between muscles; stabilized relative positions of bones
Elastic tissue
- Locations: Between vertebrae of the spinal column; ligaments supporting transitional epithelia; in blood vessel walls
- Functions: Stabilizes positions of vertebrae and penis; cushions shocks; permits expansion and contraction of organs
Dense irregular connective tissue
- Locations: Capsules of visceral organs; periostea and perichondria; nerve and muscle sheaths; dermis
- Functions: Provides strength to resist forces applied from many directions; helps prevent overexpansion of organs such as the urinary bladder
Types of Cartilage
- Hyaline Cartilage
- Elastic Cartilage
- Fibrous Cartilage
Hyaline Cartilage
- Most common type and the weakest type of Cartilage. Translucent matrix and the absence of prominent fibers
- Locations: Between tips of ribs and bones of sternum; covering bone surfaces at synovial joints; supporting larynx (voice box), trachea, and bronchi; forming part of nasal septum
- Functions: Provides stiff but somewhat flexible support; reduces friction between bony surfaces
Elastic Cartilage
- Contains numerous Elastic Fibers that make it extremely resilient and flexible
- Locations: Auricle of external ear; epiglottis; auditory canal; cuneiform Cartilages of larynx
- Functions: Provides support, but tolerates distortion without damaged and returns to original shape
Fibrous Cartilage
- Has little ground substance, may lack a perichondrium, and matrix dominated by collagen fibers
- Locations: Pads within knew joint; between pubic bones Pelvis; intervertebral discs
- Functions: Resists compression; prevents bone-to-bone contact; limits relative movement
