TissuesTissues

Chapter 3Chapter 3

Types of tissuesTypes of tissues

TissuesTissues – group of cells that have – group of cells that have specialized structural and functional specialized structural and functional rolesroles All tissues in the same type will have All tissues in the same type will have

similar functionssimilar functions 4 Types of tissue4 Types of tissue Epithelial, Connective, Muscle, Epithelial, Connective, Muscle,

NervousNervous

Epithelial tissuesEpithelial tissues They are the exposed tissues in the bodyThey are the exposed tissues in the body

Always have one surface openAlways have one surface open They are found throughout the bodyThey are found throughout the body covering organs, inner lining of body covering organs, inner lining of body

cavities, and lines hollow organscavities, and lines hollow organs Examples of where it would be?Examples of where it would be? These are very tightly packed cells, These are very tightly packed cells,

so there is little material in between so there is little material in between themthem

Epithelial tissuesEpithelial tissues

Epithelial tissues lack blood vesselsEpithelial tissues lack blood vessels How do they get nutrients?How do they get nutrients?

Nutrients are able to diffuse from the Nutrients are able to diffuse from the underlying connective tissuesunderlying connective tissues

Epithelial cells divide the fastest of any Epithelial cells divide the fastest of any tissuetissue Why would that be?Why would that be?

Functions of epithelial tissues:Functions of epithelial tissues: Main: be a protective barrierMain: be a protective barrier Secondary: secretion, absorption, and Secondary: secretion, absorption, and

sensory receptionsensory reception

Epithelial tissuesEpithelial tissues When studying the types of epithelial tissues, When studying the types of epithelial tissues,

remember:remember: SimpleSimple = Single layer, = Single layer, stratified stratified = multiple layers= multiple layers SquamousSquamous = flattened, = flattened, cuboidalcuboidal = cube, = cube, columnarcolumnar = =

columncolumn Simple Squamous EpitheliumSimple Squamous Epithelium

Single layer, flattened cellsSingle layer, flattened cells Fit tightly together (ex. Floor tiles)Fit tightly together (ex. Floor tiles) Easily damagedEasily damaged Very effective at sites of diffusionVery effective at sites of diffusion

Where would we find these?Where would we find these? Lines air sacs in lungs, lines inside of blood Lines air sacs in lungs, lines inside of blood

vesselsvessels

PicturesPictures

Simple squamousSimple squamous

Epithelial tissuesEpithelial tissues

Simple Cuboidal EpitheliumSimple Cuboidal Epithelium Small cube shaped, single layerSmall cube shaped, single layer

Covers some glands (function = Covers some glands (function = secretion)secretion)

Simple Columnar EpitheliumSimple Columnar Epithelium Column shape, single layerColumn shape, single layer

Create a very thick layerCreate a very thick layer function = protectionfunction = protection Usually secretes mucusUsually secretes mucus

PicturesPictures

Simple cuboidalSimple cuboidal simple simple columnarcolumnar

Epithelial tissuesEpithelial tissues

Pseudostratified Columnar Pseudostratified Columnar EpitheliumEpithelium

Single layer but looks like multipleSingle layer but looks like multiple Have ciliaHave cilia Line respiratory system – Why?Line respiratory system – Why?

Stratified Squamous EpitheliumStratified Squamous Epithelium Many layers, flattened cells, cells Many layers, flattened cells, cells

underneath replicate quicklyunderneath replicate quickly Forms outer layer of skinForms outer layer of skin

PicturesPictures

Pseudostratified Pseudostratified Stratified squamous Stratified squamous

Epithelial tissuesEpithelial tissues

Stratified Cuboidal EpitheliumStratified Cuboidal Epithelium Two or three layers, cube shapeTwo or three layers, cube shape

Also covers some glandsAlso covers some glands Provide more protection than single layerProvide more protection than single layer

Stratified Columnar EpitheliumStratified Columnar Epithelium Several layers, column shapedSeveral layers, column shaped

Found in reproductive tractFound in reproductive tract There are other types but we won’t There are other types but we won’t

cover thosecover those

PicturesPictures

Stratified cubiodal stratified Stratified cubiodal stratified columnarcolumnar

Epithelial TissuesEpithelial Tissues

Review:Review: Pages 86-90Pages 86-90 Pictures of each type on pages 88 – 89Pictures of each type on pages 88 – 89 When studying the types of epithelial When studying the types of epithelial

tissues, remember:tissues, remember: SimpleSimple = Single layer, = Single layer, stratified stratified = multiple layers= multiple layers SquamousSquamous = flattened, = flattened, cuboidalcuboidal = cube, = cube,

columnarcolumnar = column = column

There are 7 types that we talked aboutThere are 7 types that we talked about

AssignmentAssignment

1.1. How are Simple Squamous Epithelium like How are Simple Squamous Epithelium like floor tiles?floor tiles?

2.2. Why would Simple Columnar Epithelium Why would Simple Columnar Epithelium secrete mucus?secrete mucus?

3.3. How does Pseudostratified Columnar How does Pseudostratified Columnar Epithelium having cilia help its function?Epithelium having cilia help its function?

4.4. Rename the following types of epithelium:Rename the following types of epithelium: Single layer cube cellsSingle layer cube cells Multilayered flat cellsMultilayered flat cells Multilayered cells that are taller than they are Multilayered cells that are taller than they are

widewide

Connective TissuesConnective Tissues

What is connective tissue?What is connective tissue? The most general type of tissuesThe most general type of tissues This is a group of tissues that is very diverseThis is a group of tissues that is very diverse

They also serve several functions:They also serve several functions: Provide support, provide protection, Provide support, provide protection,

serve as a framework, fill spaces, store serve as a framework, fill spaces, store fat, produce blood cells, protect against fat, produce blood cells, protect against infections, and help repair tissue infections, and help repair tissue damagedamage

Connective TissuesConnective Tissues

In general connective tissues:In general connective tissues: Have a rich blood supply, this gives Have a rich blood supply, this gives

them plenty of nutrientsthem plenty of nutrients Are farther apart than epithelial cellsAre farther apart than epithelial cells

Why would this be?Why would this be? Not as necessary for protectionNot as necessary for protection Can divide – but not all of them are Can divide – but not all of them are

able to.able to. Contain three different types of fibersContain three different types of fibers Have six different types of tissuesHave six different types of tissues

Connective TissuesConnective Tissues

The three types of connective tissue The three types of connective tissue fibers are:fibers are:

1. 1. Collagenous FibersCollagenous Fibers – thick – thick threads of the protein threads of the protein collagencollagen

Flexible but not elasticFlexible but not elastic Have great tensile strength – useful in Have great tensile strength – useful in

areas that hold structures together areas that hold structures together where would this be?where would this be?

Ligaments and tendonsLigaments and tendons

Connective Tissue FibersConnective Tissue Fibers 2. 2. Elastic FibersElastic Fibers – Thin branching – Thin branching

fibers of the protein fibers of the protein elastinelastin Not as strong as collagen but able to Not as strong as collagen but able to

stretch.stretch. Common in body parts that need the Common in body parts that need the

ability to quickly stretch frequently (ex: ability to quickly stretch frequently (ex: vocal cords)vocal cords)

***The under layers of skin contain both of ***The under layers of skin contain both of the above types***the above types***

3. 3. Reticular FibersReticular Fibers – thin, branching – thin, branching collagenous fiberscollagenous fibers

Connective Tissue TypesConnective Tissue Types 1. 1. Loose Connective TissueLoose Connective Tissue Forms delicate, thin membranes Forms delicate, thin membranes

throughout the body.throughout the body. The cells of this tissue are a good distance The cells of this tissue are a good distance

apart apart The area between cells contains many The area between cells contains many

collagenous and elastic fiberscollagenous and elastic fibers Where would this be found?Where would this be found? It lies underneath most layers of epithelium It lies underneath most layers of epithelium

and attaches the skin to underline tissueand attaches the skin to underline tissue

Connective Tissue TypesConnective Tissue Types

2. 2. Adipose TissueAdipose Tissue Another name for this is … fat tissueAnother name for this is … fat tissue Found in many areas around the body Found in many areas around the body

including:including: Under the skin, around the kidneys, around Under the skin, around the kidneys, around

heart, behind eyeballs, in abdominal regionheart, behind eyeballs, in abdominal region What would this be used for?What would this be used for? Used to cushion some joints and organs, as Used to cushion some joints and organs, as

well as insulate the body, and store excess well as insulate the body, and store excess fatfat

Connective Tissue TypesConnective Tissue Types

3. 3. Dense connective tissueDense connective tissue Consists of many tightly packed Consists of many tightly packed

collagenous fibers, and a few elastic collagenous fibers, and a few elastic fibersfibers

Would this tissue be strong or weak?Would this tissue be strong or weak? StrongStrong Used to connect structures togetherUsed to connect structures together Where would this be found?Where would this be found? Ligaments and tendons are the most Ligaments and tendons are the most

common areascommon areas

Connective Tissue TypesConnective Tissue Types 4. 4. CartilageCartilage Rigid connective tissue, used mainly for Rigid connective tissue, used mainly for

supportsupport Found all over the body (joints, ears, nose, etc.)Found all over the body (joints, ears, nose, etc.) Does not have a direct blood supplyDoes not have a direct blood supply How does this affect how cartilage is repaired?How does this affect how cartilage is repaired? 3 types of cartilage3 types of cartilage

Hyaline cartilage – Hyaline cartilage – found in nose, trachea, some found in nose, trachea, some jointsjoints

Elastic cartilage – Elastic cartilage – framework for external ear, larynxframework for external ear, larynx Fibrocartilage – toughest, found in spine, and kneesFibrocartilage – toughest, found in spine, and knees

Connective TissueConnective Tissue 5. Bone5. Bone Most rigid connective tissueMost rigid connective tissue This is due to the mineral deposits This is due to the mineral deposits

between cellsbetween cells Very well supplied with blood, therefore it Very well supplied with blood, therefore it

heals much quicker than cartilageheals much quicker than cartilage Where is this located?Where is this located? All throughout the body in bonesAll throughout the body in bones What are the functions?What are the functions? Support, protection, production of blood Support, protection, production of blood

cells, storage of mineralscells, storage of minerals

Connective TissueConnective Tissue

6. Blood6. Blood Functions: transports substances, Functions: transports substances,

exchange of gases, help maintain exchange of gases, help maintain homeostasishomeostasis

Found all throughout the body within Found all throughout the body within the blood vesselsthe blood vessels

Composed of:Composed of: Red blood cellsRed blood cells White blood cellsWhite blood cells PlateletsPlatelets PlasmaPlasma

Connective TissueConnective Tissue ReviewReview Most general category of tissues, many Most general category of tissues, many

usesuses Table 5.4 on page 109Table 5.4 on page 109 Collagen Fibers – used for?Collagen Fibers – used for? Elastic Fibers – used for?Elastic Fibers – used for? Reticular Fibers – used for?Reticular Fibers – used for? Six types of tissues:Six types of tissues: Loose, Adipose, Dense, Cartilage, Bone, Loose, Adipose, Dense, Cartilage, Bone,

BloodBlood

Muscle TissueMuscle Tissue

Not as diverse as a groupNot as diverse as a group Muscle tissues are Muscle tissues are contractilecontractile What does that mean to you?What does that mean to you? The cells are elongated and they can The cells are elongated and they can

shortenshorten As each cell shortens, it shortens the As each cell shortens, it shortens the

tissue, thus moving the body parttissue, thus moving the body part Three types of muscle tissueThree types of muscle tissue Pictures --- Pg. 110 – 111Pictures --- Pg. 110 – 111 Table 5.5 on pg. 112Table 5.5 on pg. 112

Muscle TissueMuscle Tissue

1. 1. Skeletal Muscle TissueSkeletal Muscle Tissue This is the kind that most people think of.This is the kind that most people think of. Found in muscles that attach to bonesFound in muscles that attach to bones These enable use to talk, throw, walk, etc.These enable use to talk, throw, walk, etc. Controlled by conscious effort (voluntary)Controlled by conscious effort (voluntary) Have striationsHave striations StriationsStriations – alternating light and dark – alternating light and dark

regionsregions

Muscle TissueMuscle Tissue

Muscle TissueMuscle Tissue

2. Smooth Muscle Tissue2. Smooth Muscle Tissue Lacks striations – therefore it looks smoothLacks striations – therefore it looks smooth Shorter than skeletal muscleShorter than skeletal muscle Found in the walls of hollow organsFound in the walls of hollow organs Examples: stomach, intestines, bladder, Examples: stomach, intestines, bladder,

etc.etc. Cannot be stimulated by conscious effort Cannot be stimulated by conscious effort

(involuntary)(involuntary) Example: movement of food through the Example: movement of food through the

digestive systemdigestive system

Muscle TissueMuscle Tissue

Muscle TissueMuscle Tissue

3. 3. Cardiac Muscle TissueCardiac Muscle Tissue Striated – but differently than skeletal Striated – but differently than skeletal

musclemuscle Found only in the heart (cardiac = heart)Found only in the heart (cardiac = heart) This tissue forms most of the heartThis tissue forms most of the heart Voluntary or involuntary?Voluntary or involuntary? Cells are connected by intercolated disksCells are connected by intercolated disks

This allows for all cells to fire at onceThis allows for all cells to fire at once Why would this be important?Why would this be important?

Muscle TissueMuscle Tissue

Nervous TissueNervous Tissue

Where are they found?Where are they found? Nerves, brain, spinal cordNerves, brain, spinal cord Functions:Functions: Transport messages throughout the Transport messages throughout the

body, to and from the brainbody, to and from the brain Stimulate muscles for movementStimulate muscles for movement Coordinate other bodily functionsCoordinate other bodily functions

AssignmentAssignment

Pg 114Pg 114 RE 2, 14, 16, 20, 22 RE 2, 14, 16, 20, 22 CT 4CT 4