Tissues Chapter 3

Types of tissues Tissues – group of cells that have specialized structural and functional roles Tissues – group of cells that have specialized structural and functional roles All tissues in the same type will have similar functions All tissues in the same type will have similar functions 4 Types of tissue 4 Types of tissue Epithelial, Connective, Muscle, Nervous Epithelial, Connective, Muscle, Nervous

Epithelial tissues They are the exposed tissues in the body They are the exposed tissues in the body Always have one surface open Always have one surface open They are found throughout the body They are found throughout the body covering organs, inner lining of body cavities, and lines hollow organs covering organs, inner lining of body cavities, and lines hollow organs Examples of where it would be? Examples of where it would be? These are very tightly packed cells, so there is little material in between them These are very tightly packed cells, so there is little material in between them

Epithelial tissues Epithelial tissues lack blood vessels Epithelial tissues lack blood vessels How do they get nutrients? How do they get nutrients? Nutrients are able to diffuse from the underlying connective tissues Nutrients are able to diffuse from the underlying connective tissues Epithelial cells divide the fastest of any tissue Epithelial cells divide the fastest of any tissue Why would that be? Why would that be? Functions of epithelial tissues: Functions of epithelial tissues: Main: be a protective barrier Main: be a protective barrier Secondary: secretion, absorption, and sensory reception Secondary: secretion, absorption, and sensory reception

Epithelial tissues When studying the types of epithelial tissues, remember: When studying the types of epithelial tissues, remember: Simple = Single layer, stratified = multiple layers Simple = Single layer, stratified = multiple layers Squamous = flattened, cuboidal = cube, columnar = column Squamous = flattened, cuboidal = cube, columnar = column Simple Squamous Epithelium Simple Squamous Epithelium Single layer, flattened cells Single layer, flattened cells Fit tightly together (ex. Floor tiles) Fit tightly together (ex. Floor tiles) Easily damaged Easily damaged Very effective at sites of diffusion Very effective at sites of diffusion Where would we find these? Where would we find these? Lines air sacs in lungs, lines inside of blood vessels Lines air sacs in lungs, lines inside of blood vessels

Pictures Simple squamous Simple squamous

Epithelial tissues Simple Cuboidal Epithelium Simple Cuboidal Epithelium Small cube shaped, single layer Small cube shaped, single layer Covers some glands (function = secretion) Covers some glands (function = secretion) Simple Columnar Epithelium Simple Columnar Epithelium Column shape, single layer Column shape, single layer Create a very thick layer Create a very thick layer function = protection function = protection Usually secretes mucus Usually secretes mucus

Pictures Simple cuboidal simple columnar Simple cuboidal simple columnar

Epithelial tissues Pseudostratified Columnar Epithelium Pseudostratified Columnar Epithelium Single layer but looks like multiple Single layer but looks like multiple Have cilia Have cilia Line respiratory system – Why? Line respiratory system – Why? Stratified Squamous Epithelium Stratified Squamous Epithelium Many layers, flattened cells, cells underneath replicate quickly Many layers, flattened cells, cells underneath replicate quickly Forms outer layer of skin Forms outer layer of skin

Pictures Pseudostratified Stratified squamous Pseudostratified Stratified squamous

Epithelial tissues Stratified Cuboidal Epithelium Stratified Cuboidal Epithelium Two or three layers, cube shape Two or three layers, cube shape Also covers some glands Also covers some glands Provide more protection than single layer Provide more protection than single layer Stratified Columnar Epithelium Stratified Columnar Epithelium Several layers, column shaped Several layers, column shaped Found in reproductive tract Found in reproductive tract There are other types but we won’t cover those There are other types but we won’t cover those

Pictures Stratified cubiodal stratified columnar Stratified cubiodal stratified columnar

Epithelial Tissues Review: Review: Pages Pages Pictures of each type on pages 88 – 89 Pictures of each type on pages 88 – 89 When studying the types of epithelial tissues, remember: When studying the types of epithelial tissues, remember: Simple = Single layer, stratified = multiple layers Simple = Single layer, stratified = multiple layers Squamous = flattened, cuboidal = cube, columnar = column Squamous = flattened, cuboidal = cube, columnar = column There are 7 types that we talked about There are 7 types that we talked about

Assignment 1. How are Simple Squamous Epithelium like floor tiles? 2. Why would Simple Columnar Epithelium secrete mucus? 3. How does Pseudostratified Columnar Epithelium having cilia help its function? 4. Rename the following types of epithelium: Single layer cube cells Single layer cube cells Multilayered flat cells Multilayered flat cells Multilayered cells that are taller than they are wide Multilayered cells that are taller than they are wide

Connective Tissues What is connective tissue? What is connective tissue? The most general type of tissues The most general type of tissues This is a group of tissues that is very diverse This is a group of tissues that is very diverse They also serve several functions: They also serve several functions: Provide support, provide protection, serve as a framework, fill spaces, store fat, produce blood cells, protect against infections, and help repair tissue damage Provide support, provide protection, serve as a framework, fill spaces, store fat, produce blood cells, protect against infections, and help repair tissue damage

Connective Tissues In general connective tissues: In general connective tissues: Have a rich blood supply, this gives them plenty of nutrients Have a rich blood supply, this gives them plenty of nutrients Are farther apart than epithelial cells Are farther apart than epithelial cells Why would this be? Why would this be? Not as necessary for protection Not as necessary for protection Can divide – but not all of them are able to. Can divide – but not all of them are able to. Contain three different types of fibers Contain three different types of fibers Have six different types of tissues Have six different types of tissues

Connective Tissues The three types of connective tissue fibers are: The three types of connective tissue fibers are: 1. Collagenous Fibers – thick threads of the protein collagen 1. Collagenous Fibers – thick threads of the protein collagen Flexible but not elastic Flexible but not elastic Have great tensile strength – useful in areas that hold structures together Have great tensile strength – useful in areas that hold structures together where would this be? where would this be? Ligaments and tendons Ligaments and tendons

Connective Tissue Fibers 2. Elastic Fibers – Thin branching fibers of the protein elastin 2. Elastic Fibers – Thin branching fibers of the protein elastin Not as strong as collagen but able to stretch. Not as strong as collagen but able to stretch. Common in body parts that need the ability to quickly stretch frequently (ex: vocal cords) Common in body parts that need the ability to quickly stretch frequently (ex: vocal cords) ***The under layers of skin contain both of the above types*** ***The under layers of skin contain both of the above types*** 3. Reticular Fibers – thin, branching collagenous fibers 3. Reticular Fibers – thin, branching collagenous fibers

Connective Tissue Types 1. Loose Connective Tissue 1. Loose Connective Tissue Forms delicate, thin membranes throughout the body. Forms delicate, thin membranes throughout the body. The cells of this tissue are a good distance apart The cells of this tissue are a good distance apart The area between cells contains many collagenous and elastic fibers The area between cells contains many collagenous and elastic fibers Where would this be found? Where would this be found? It lies underneath most layers of epithelium and attaches the skin to underline tissue It lies underneath most layers of epithelium and attaches the skin to underline tissue

Connective Tissue Types 2. Adipose Tissue 2. Adipose Tissue Another name for this is … fat tissue Another name for this is … fat tissue Found in many areas around the body including: Found in many areas around the body including: Under the skin, around the kidneys, around heart, behind eyeballs, in abdominal region Under the skin, around the kidneys, around heart, 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 well as insulate the body, and store excess fat Used to cushion some joints and organs, as well as insulate the body, and store excess fat

Connective Tissue Types 3. Dense connective tissue 3. Dense connective tissue Consists of many tightly packed collagenous fibers, and a few elastic fibers Consists of many tightly packed collagenous fibers, and a few elastic fibers Would this tissue be strong or weak? Would this tissue be strong or weak? Strong Strong Used to connect structures together Used to connect structures together Where would this be found? Where would this be found? Ligaments and tendons are the most common areas Ligaments and tendons are the most common areas

Connective Tissue Types 4. Cartilage 4. Cartilage Rigid connective tissue, used mainly for support Rigid connective tissue, used mainly for support Found all over the body (joints, ears, nose, etc.) Found all over the body (joints, ears, nose, etc.) Does not have a direct blood supply Does 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 cartilage 3 types of cartilage Hyaline cartilage – found in nose, trachea, some joints Hyaline cartilage – found in nose, trachea, some joints Elastic cartilage – framework for external ear, larynx Elastic cartilage – framework for external ear, larynx Fibrocartilage – toughest, found in spine, and knees Fibrocartilage – toughest, found in spine, and knees

Connective Tissue 5. Bone 5. Bone Most rigid connective tissue Most rigid connective tissue This is due to the mineral deposits between cells This is due to the mineral deposits between cells Very well supplied with blood, therefore it heals much quicker than cartilage Very well supplied with blood, therefore it heals much quicker than cartilage Where is this located? Where is this located? All throughout the body in bones All throughout the body in bones What are the functions? What are the functions? Support, protection, production of blood cells, storage of minerals Support, protection, production of blood cells, storage of minerals

Connective Tissue 6. Blood 6. Blood Functions: transports substances, exchange of gases, help maintain homeostasis Functions: transports substances, exchange of gases, help maintain homeostasis Found all throughout the body within the blood vessels Found all throughout the body within the blood vessels Composed of: Composed of: Red blood cells Red blood cells White blood cells White blood cells Platelets Platelets Plasma Plasma

Connective Tissue Review Review Most general category of tissues, many uses Most general category of tissues, many uses Table 5.4 on page 109 Table 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, Blood Loose, Adipose, Dense, Cartilage, Bone, Blood

Muscle Tissue Not as diverse as a group Not as diverse as a group Muscle tissues are contractile Muscle tissues are contractile What does that mean to you? What does that mean to you? The cells are elongated and they can shorten The cells are elongated and they can shorten As each cell shortens, it shortens the tissue, thus moving the body part As each cell shortens, it shortens the tissue, thus moving the body part Three types of muscle tissue Three types of muscle tissue Pictures --- Pg. 110 – 111 Pictures --- Pg. 110 – 111 Table 5.5 on pg. 112 Table 5.5 on pg. 112

Muscle Tissue 1. Skeletal Muscle Tissue 1. Skeletal 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 bones Found 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 striations Have striations Striations – alternating light and dark regions Striations – alternating light and dark regions

Muscle Tissue

2. Smooth Muscle Tissue 2. Smooth Muscle Tissue Lacks striations – therefore it looks smooth Lacks striations – therefore it looks smooth Shorter than skeletal muscle Shorter than skeletal muscle Found in the walls of hollow organs Found in the walls of hollow organs Examples: stomach, intestines, bladder, etc. Examples: stomach, intestines, bladder, etc. Cannot be stimulated by conscious effort (involuntary) Cannot be stimulated by conscious effort (involuntary) Example: movement of food through the digestive system Example: movement of food through the digestive system

Muscle Tissue

3. Cardiac Muscle Tissue 3. Cardiac Muscle Tissue Striated – but differently than skeletal muscle Striated – but differently than skeletal muscle Found only in the heart (cardiac = heart) Found only in the heart (cardiac = heart) This tissue forms most of the heart This tissue forms most of the heart Voluntary or involuntary? Voluntary or involuntary? Cells are connected by intercolated disks Cells are connected by intercolated disks This allows for all cells to fire at once This allows for all cells to fire at once Why would this be important? Why would this be important?

Muscle Tissue

Nervous Tissue Where are they found? Where are they found? Nerves, brain, spinal cord Nerves, brain, spinal cord Functions: Functions: Transport messages throughout the body, to and from the brain Transport messages throughout the body, to and from the brain Stimulate muscles for movement Stimulate muscles for movement Coordinate other bodily functions Coordinate other bodily functions

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