Chapter 5 Chapter 5 TissuesTissues

How is it all Connected?How is it all Connected?

Cells = basic unit of lifeCells = basic unit of life

Cells come together to form TISSUESCells come together to form TISSUES

TISSUES come together to form ORGANSTISSUES come together to form ORGANS

ORGANS come together to form SYSTEMSORGANS come together to form SYSTEMS

SYSTEMS come together to form US.SYSTEMS come together to form US.

So what is a TISSUE?So what is a TISSUE?

““Layers or groups of SIMILAR cells with a Layers or groups of SIMILAR cells with a COMMON function.”COMMON function.”

Tissues are distinguished from each other Tissues are distinguished from each other because of differences in size, organization, because of differences in size, organization, and functionand function

Can you think of anything that would be Can you think of anything that would be considered a TISSUE?considered a TISSUE?

BLOODBLOOD

MUSCULE TISSUEMUSCULE TISSUE

SMOOTH TISSUESMOOTH TISSUE

SMOOTH TISSUESMOOTH TISSUE

BONEBONE

CARTILAGECARTILAGE

NERVOUS TISSUENERVOUS TISSUE

4 TYPES OF TISSUES4 TYPES OF TISSUES

Epithelial TissuesEpithelial Tissues: : Covers the body’s surface and organs.Covers the body’s surface and organs. Connective TissuesConnective Tissues: : Tendons, ligaments, cartilage, blood, fat, boneTendons, ligaments, cartilage, blood, fat, bone Muscle TissuesMuscle Tissues:: Skeletal Muscles, heart, smooth muscleSkeletal Muscles, heart, smooth muscle Nervous TissuesNervous Tissues:: Brain, spinal cord, nervesBrain, spinal cord, nerves

EPITHELIAL TISSUESEPITHELIAL TISSUES

So if Epithelial tissues are on the body surface So if Epithelial tissues are on the body surface and surround the organs, then what do you and surround the organs, then what do you think this type of tissue’s function is?think this type of tissue’s function is?

Protection: Example?Protection: Example? Secretion: Example?Secretion: Example? Absorption: Example?Absorption: Example? Excretion: Example?Excretion: Example?

EPITHELIAL TISSUESEPITHELIAL TISSUES

Where are they located?Where are they located? Surface of the bodySurface of the body Cover the internal organsCover the internal organs Compose the glandsCompose the glands

Distinguishing Characteristics?Distinguishing Characteristics? No blood vessels. Why do you think?No blood vessels. Why do you think? Cells divide rapidly. Why is this good?Cells divide rapidly. Why is this good? Cells are tightly packed. How does this help us?Cells are tightly packed. How does this help us?

EPITHELIAL TISSUESEPITHELIAL TISSUES

Epithelial Tissues are classified by the shape Epithelial Tissues are classified by the shape of their cells.of their cells.

There are 3 different epithelial tissue cell typesThere are 3 different epithelial tissue cell types 1. 1. SquamousSquamous: flattened cells: flattened cells

2. 2. CuboidalCuboidal: Cube-like cells: Cube-like cells

3. 3. ColumnarColumnar: Elongated: Elongated

EPITHELIAL TISSUESEPITHELIAL TISSUES

The arrangement of these cells varies.The arrangement of these cells varies. There are two different ways to arrange There are two different ways to arrange

Epithelial TissuesEpithelial Tissues

1.1. SimpleSimple: one layer of cells. : one layer of cells.

2. 2. StratifiedStratified: two or more layers of cells.: two or more layers of cells.

Types of Epithelial TissuesTypes of Epithelial Tissues

There are eight different types of Epithelial There are eight different types of Epithelial tissues.tissues.

When you refer to one type of Epithelial tissue When you refer to one type of Epithelial tissue you call it an Epithelium (this is the singular you call it an Epithelium (this is the singular spelling).spelling).

Example: Example: Simple Squamous Simple Squamous EpitheliumEpithelium What can you tell me about the name above What can you tell me about the name above

based on what you just learned?based on what you just learned?

Connective TissuesConnective Tissues **Comprise much of the body **Comprise much of the body **The most abundant type of tissue by weight.**The most abundant type of tissue by weight. 1. bind structures1. bind structures 2. provide support and protection2. provide support and protection 3. serve as a framework3. serve as a framework 4. fill spaces4. fill spaces 5. store fat5. store fat 6. produce blood cells6. produce blood cells 7. protect against infection7. protect against infection 8. help repair tissue damage.8. help repair tissue damage.

Major Connective Tissue Cell Major Connective Tissue Cell TYPESTYPES

1. Fixed cells: reside in the tissue for extended 1. Fixed cells: reside in the tissue for extended period of timeperiod of time

Example: fibroblast = large star shaped p.152Example: fibroblast = large star shaped p.152

2. Wandering Cells: appear in tissues 2. Wandering Cells: appear in tissues temporarily in response to injury or infection.temporarily in response to injury or infection.

Example: Mast cells = release histamine that Example: Mast cells = release histamine that dialates capillaries = swelling and redness.dialates capillaries = swelling and redness.

Categories of Connective TissueCategories of Connective Tissue

1. Loose Connective Tissue: binds the skin to 1. Loose Connective Tissue: binds the skin to the muscle tissue below the muscle tissue below

2. Adipose Tissue: = fat2. Adipose Tissue: = fat These cells accumulate fat, they enlarge and These cells accumulate fat, they enlarge and

their nuclei is pushed to one sidetheir nuclei is pushed to one side When they become too abundant they crowd When they become too abundant they crowd

out other cell types and form “adipose tissue”out other cell types and form “adipose tissue” Found: between muscles, around kidneys, Found: between muscles, around kidneys,

behind eyeballs, surface of the heart, and behind eyeballs, surface of the heart, and around joints.around joints.

Adipose tissueAdipose tissue

3. Reticular connective tissue: provides the 3. Reticular connective tissue: provides the framework for some internal organs (spleen, framework for some internal organs (spleen, liver, lymphatic organs.liver, lymphatic organs.

They have collagen They have collagen fibersfibers

4. Dense Connective Tissue: tendons and 4. Dense Connective Tissue: tendons and ligamentsligaments

Very strong and can withstand pulling forces.Very strong and can withstand pulling forces. Binds body parts togetherBinds body parts together Has poor blood supply and is very slow to Has poor blood supply and is very slow to

heal.heal. This is why sprains, damage to tissue around This is why sprains, damage to tissue around

joints, takes considerable time to heal.joints, takes considerable time to heal.

Dense Connective TissueDense Connective Tissue

P.158P.158

5. Elastic Connective Tissue: found in the 5. Elastic Connective Tissue: found in the attachments between bones of the spinal attachments between bones of the spinal column.column.

Very rareVery rare in the body but are found in large in the body but are found in large arteries such as the aorta.arteries such as the aorta.

http://www.austincc.edu/histologyhelp/tissues/http://www.austincc.edu/histologyhelp/tissues/tn_elas_ct.htmltn_elas_ct.html

6. Cartilage: rigid, provides support, 6. Cartilage: rigid, provides support, framework, attachments, provides a structural framework, attachments, provides a structural model for many developing bones.model for many developing bones.

Contains a large volume of waterContains a large volume of water Lacks a direct blood supply, blood vessels Lacks a direct blood supply, blood vessels

surround it, obtain nutrients by diffusionsurround it, obtain nutrients by diffusion This is why torn cartilage heals so slowlyThis is why torn cartilage heals so slowly

3 types of cartilage3 types of cartilage

1. Hyaline: most common, tips of bones at 1. Hyaline: most common, tips of bones at joints, soft part of the nose, supporting rings of joints, soft part of the nose, supporting rings of the trachea. Prominent in early development.the trachea. Prominent in early development.

2. Elastic: more flexible, ears and larynx2. Elastic: more flexible, ears and larynx 3. Fibrocartilage: very tough, shock absorber, 3. Fibrocartilage: very tough, shock absorber,

intervertebral discs, knees and pelvis.intervertebral discs, knees and pelvis.

7. Bone:7. Bone: Most rigid connective tissueMost rigid connective tissue Internally supports body structuresInternally supports body structures Very active tissueVery active tissue Heals much more rapidly than injured cartilage Heals much more rapidly than injured cartilage

because of close access to a blood supplybecause of close access to a blood supply

8. Blood8. Blood Cells suspended in fluid called PLASMACells suspended in fluid called PLASMA 1. Red blood cells: transport gases1. Red blood cells: transport gases 2. White blood cells: fight infection2. White blood cells: fight infection 3. Platelets: cause blood clotting3. Platelets: cause blood clotting Where do blood cells form?Where do blood cells form?