Transcript Connective Tissue

Connective Tissue Components
 3 major components of connective tissue:
 Extracellular fibers, Ground substance, Cells
 _______________ ________ = Extracellular fibers + Ground substance
 Matrix surrounds and separates the cells, providing important structural
and nutritional support to them, allowing them to be farther apart than
epithelial cells.
 1. Ground substance
 Liquid, solid, or gel
 2. Extracellular fibers
 Collagenous, Reticular, Elastic
 3. Cells
 Fixed cells
Fibroblasts, Adipocytes (fat cells), Reticular cells
 Wandering 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 Tissue
 Collagenous:
 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 Tissue
 Reticular:
 Composed of collagen
 Thin, delicate, ____________ into
complicated networks.
 Form support around highly ____________
organs
 endocrine glands, lymph nodes, spleen, bone marrow,
liver
 Elastic:
 Composed primarily of protein ________.
 Are branched and form networks
 Can 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 tissue
 Produce and maintain the __________
 Fibroblast:
secrete fibers and ground substance of the matrix
 Can 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, fibrocyte
o Can revert back to blast if more matrix is needed.
Major Cell Types of Connective Tissue
 Fixed cells continued.
 Adipose cells/Adipocytes:
 Found throughout connective tissue
 Resemble 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 cells
 Manufacture 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 tissue
 Usually 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 lysosomes
 drawn to sites of infection where they engulf
invaders
Types of Connective Tissue
 Connective Tissue Proper:
 Loose Connective Tissue- supports structures that it surrounds
 Areolar, Adipose, Reticular
 Dense Connective Tissue- highly fibrous (collagen); little vascularization,
ground substance, or cells; reinforces and binds structures
 Dense regular, Dense irregular, Elastic
 Specialized Connective Tissue:
 Cartilage
 Hyaline, Elastic, Fibrocartilage
 Bone
 Compact, Cancellous
 Blood
Loose Connective
Tissue: Areolar
 Most common type of connective tissue
 Surrounds every organ
 Acts 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 body
 Adipocytes change from resembling fibroblasts
to filling with lipid
 Brown:
 Found in _________ and ____________ animals
 Site of heat production, temperature regulation
Loose Connective Tissue: Adipose
Loose Connective Tissue: Reticular
 Framework for spleen, liver, lymph
nodes, bone marrow
 Called _________
 Contains only one type of fiber:
___________
 Many fibroblasts
 Makes 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: Regular
 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: Irregular
 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.
Dense Connective
Tissue: Elastic
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 Cartilage
 Hyaline 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 Cartilage
 Similar to hyaline cartilage but contains _________ fibers
 Give 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
 Structure
 Matrix – 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 osteoblasts
 Remodel 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 (________)