Connective Tissue Components

3 major components of connective tissue:

Extracellular fibers, Ground substance, Cells_______________ ________ = Extracellular fibers + Ground

substanceMatrix surrounds and separates the cells, providing

important structural and nutritional support to them, allowing them to be farther apart than epithelial cells.

1. Ground substanceLiquid, solid, or gel

2. Extracellular fibersCollagenous, Reticular, Elastic

3. CellsFixed cells

Fibroblasts, Adipocytes (fat cells), Reticular cellsWandering cells

Mast cells, Leukocytes (white blood cells), Macrophages (fixed and wandering)

Connective Tissue Components: Ground Substance

Composed of glycoproteins called __________________ (GAGs)

hyaluronic acid

Help to orient fiber formation in connective tissue.

Is medium through which cells exchange nutrients and waste with the __________ ___________.

Acts as shock absorbing cushion and helps to protect the delicate cells that it surrounds.

Fibers of Connective TissueCollagenous:

Most common fiber found in the body

Strong, thick bands organized into bundles, composed of ____________ (structural protein).

Resist ___________ forces, so they are found in tendons and ligaments that are continuously being pulled and stretched.wavy appearance when not

stretched

Fibers of Connective TissueReticular:

Composed of collagenThin, delicate, ____________ into

complicated networks.Form support around highly

____________ organsendocrine glands, lymph nodes, spleen,

bone marrow, liver

Elastic:Composed primarily of protein

________.Are branched and form networksCan stretch and contract.Found in tissues that stretch: vocal

cords, lungs, skin, blood vessel walls.

Major Cell Types of Connective Tissue

Fixed Cells:Remain in the connective tissueProduce and maintain the __________

Fibroblast:secrete fibers and ground substance of the matrixCan reproduce and are metabolically active.Name is based on _________.

o Chondroblast (cartilage), osteoblast (bone), etc.

As the cells mature and the matrix is formed, cells become less active and suffix is changed to –_______. o Chondrocyte, osteocyte, fibrocyteo Can revert back to blast if more matrix is needed.

Major Cell Types of Connective TissueFixed cells continued.

Adipose cells/Adipocytes:Found throughout connective tissueResemble fibroblasts early on, but as

they age they become filled with lipid and swell.__________ gets pushed to the side

Adipocytes clustered together form _________ tissue.found all over, but is prominent under

the skin and in the abdomen

Reticular Cells:Flat, star-shaped cells that form net-

like connections with other cellsManufacture reticular fibers.Found in tissues of the immune system:

lymph nodes, spleen, bone marrow

Major Cell Types of Connective Tissue

Wandering Cells:Move in and out of connective tissue as needed. Help _______ and _________ the tissue

Leukoctyes: (white blood cells)Found in blood, move into connective tissue during periods of

infection/inflammation.Squeeze through the simple squamous epithelium of blood vessels

(diapedesis) Important in immune function- engulf and digest invaders or

produce antibodies against them

Mast cells Carry histamine and heparin granules which initiate

inflammatory response when released into tissueUsually found near blood vessels

Major Cell Types of Connective Tissue

Wandering cells continued..

Macrophages:

___________ scavengers that may be either fixed or transient in connective tissue.

Engulf microbes, dead cells and debris that are digested by the macrophage’s lysosomesdrawn to sites of infection where

they engulf invaders

Types of Connective TissueConnective Tissue Proper:

Loose Connective Tissue- supports structures that it surroundsAreolar, Adipose, Reticular

Dense Connective Tissue- highly fibrous (collagen); little vascularization, ground substance, or cells; reinforces and binds structuresDense regular, Dense irregular, Elastic

Specialized Connective Tissue:Cartilage

Hyaline, Elastic, FibrocartilageBone

Compact, CancellousBlood

Loose Connective

Tissue: Areolar

Most common type of connective tissueSurrounds every organActs to support and cushion

organs and other delicate structures.

Predominant cell is ____________.

Has “_______” spaces that are filled with fluid and viscous ground substance

Filling of open spaces during trauma is called __________

Commonly known as ________ Found beneath skin, in bone marrow, in abdomen Energy storage, insulator, shock absorber Highly vascularized areolar tissue in which adipocytes

predominate Cells __________/__________ based on amount of lipid being stored in

them.

May be classified as:

White:Found throughout bodyAdipocytes change from resembling fibroblasts to filling with lipid

Brown:Found in _________ and ____________ animalsSite of heat production, temperature regulationLoose Connective Tissue:

Adipose

Loose Connective Tissue: Reticular

Framework for spleen, liver, lymph nodes, bone marrowCalled _________

Contains only one type of fiber: ___________

Many fibroblasts

Dense Connective

Tissue: RegularMakes up tendons and

ligaments, fascia

Tightly packed,__________ collagen fibers

Little vascularization, slow to heal

Little ground substance

Fibroblasts line the collagen bundles

Resists strong pulling forces in _____ direction.

Dense Connective

Tissue: Irregular

Found in dermis, organ capsules

Forms tough capsule of joints.

Collagen fibers in thicker bundles than those in dense regular connective tissue.

Sheets of collagen in ___________ directions.

Single sheet that can withstand pulling force from _______ different directions.

Dense Connective Tissue: Elastic

Found in areas of the body that require ___________:Stomach, artery

walls, bladder

Beneath transitional epithelium in urinary tract

High concentration of elastic fibers (more than collagen) that are extremely flexible.

Specialized Connective Tissue: Cartilage

More rigid than dense connective tissue, more flexible than bone.

Prevents bones from rubbing against each other.

Does not contain nerves or blood vessels.Receives nutrition from ________________.

Chondrocytes live in pockets called _______

3 types of cartilage:Hyaline cartilage, Elastic Cartilage, Fibrocartilage

Specialized Connective Tissue: Types of CartilageHyaline Cartilage

Most common type of cartilage found in body.Found as ____________ cartilage at end of long

bones and joints and connects ribs to the sternum.

Most rigid type of cartilage.Closely packed collagen fibers that make it

tough but more flexible than bone.

Elastic CartilageSimilar to hyaline cartilage but contains

_________ fibersGive it flexibility, ability to bend

Found in pinnae, epiglottis

Specialized Connective Tissue: Types of Cartilage

Fibrocartilage

Found between vertebrae, in pelvis, and in knee joint

Able to handle compression, absorbs ______

Thick bundles of collagen, but few chondrocytes

Specialized Connective Tissue: Bone

Also called osseous connective tissue Hardest and most rigid type of

connective tissue

StructureMatrix – collagen fibers and calcium

salts____________- tiny channels through

matrix that allows osteocytes to communicate

_________- chambers where osteocytes reside

Blood Supply- __________ canals (channels in bone that carry blood supply and nerves)

Cells- Osteoclasts and osteoblastsRemodel bone as needed

Specialized Connective Tissue: Blood

Most atypical type of connective tissue.

Carries nutrients and gases through the body

Matrix: _______ (plasma) Fibers: few and only visible in

a _____Cells:

Erythrocytes (______ blood cells)Leukocytes (________ blood cells)Thrombocytes (________)