Chapter 5 Tissues

How is it all Connected? Cells = basic unit of life Cells = basic unit of life Cells come together to form TISSUES Cells come together to form TISSUES TISSUES come together to form ORGANS TISSUES come together to form ORGANS ORGANS come together to form SYSTEMS ORGANS come together to form SYSTEMS SYSTEMS come together to form US. SYSTEMS come together to form US.

So what is a TISSUE? “Layers or groups of SIMILAR cells with a COMMON function.” “Layers or groups of SIMILAR cells with a COMMON function.” Tissues are distinguished from each other because of differences in size, organization, and function Tissues are distinguished from each other because of differences in size, organization, and function Can you think of anything that would be considered a TISSUE? Can you think of anything that would be considered a TISSUE?

BLOOD

MUSCULE TISSUE

SMOOTH TISSUE

BONE

CARTILAGE

NERVOUS TISSUE

4 TYPES OF TISSUES Epithelial Tissues: Epithelial Tissues: Covers the body’s surface and organs. Covers the body’s surface and organs. Connective Tissues: Connective Tissues: Tendons, ligaments, cartilage, blood, fat, bone Tendons, ligaments, cartilage, blood, fat, bone Muscle Tissues: Muscle Tissues: Skeletal Muscles, heart, smooth muscle Skeletal Muscles, heart, smooth muscle Nervous Tissues: Nervous Tissues: Brain, spinal cord, nerves Brain, spinal cord, nerves

EPITHELIAL TISSUES So if Epithelial tissues are on the body surface and surround the organs, then what do you think this type of tissue’s function is? So if Epithelial tissues are on the body surface and surround the organs, then what do you 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 TISSUES Where are they located? Where are they located? Surface of the body Surface of the body Cover the internal organs Cover the internal organs Compose the glands Compose 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 TISSUES Epithelial Tissues are classified by the shape of their cells. Epithelial Tissues are classified by the shape of their cells. There are 3 different epithelial tissue cell types There are 3 different epithelial tissue cell types 1. Squamous: flattened cells 1. Squamous: flattened cells 2. Cuboidal: Cube-like cells 2. Cuboidal: Cube-like cells 3. Columnar: Elongated 3. Columnar: Elongated

EPITHELIAL TISSUES The arrangement of these cells varies. The arrangement of these cells varies. There are two different ways to arrange Epithelial Tissues There are two different ways to arrange Epithelial Tissues 1. Simple: one layer of cells. 1. Simple: one layer of cells. 2. Stratified: two or more layers of cells. 2. Stratified: two or more layers of cells.

Types of Epithelial Tissues There are eight different types of Epithelial tissues. There are eight different types of Epithelial tissues. When you refer to one type of Epithelial tissue you call it an Epithelium (this is the singular spelling). When you refer to one type of Epithelial tissue you call it an Epithelium (this is the singular spelling). Example: Simple Squamous Epithelium Example: Simple Squamous Epithelium What can you tell me about the name above based on what you just learned? What can you tell me about the name above based on what you just learned?

Connective 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 structures 1. bind structures 2. provide support and protection 2. provide support and protection 3. serve as a framework 3. serve as a framework 4. fill spaces 4. fill spaces 5. store fat 5. store fat 6. produce blood cells 6. produce blood cells 7. protect against infection 7. protect against infection 8. help repair tissue damage. 8. help repair tissue damage.

Major Connective Tissue Cell TYPES 1. Fixed cells: reside in the tissue for extended period of time 1. Fixed cells: reside in the tissue for extended period of time Example: fibroblast = large star shaped p.152 Example: fibroblast = large star shaped p Wandering Cells: appear in tissues temporarily in response to injury or infection. 2. Wandering Cells: appear in tissues temporarily in response to injury or infection. Example: Mast cells = release histamine that dialates capillaries = swelling and redness. Example: Mast cells = release histamine that dialates capillaries = swelling and redness.

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

2. Adipose Tissue: = fat 2. Adipose Tissue: = fat These cells accumulate fat, they enlarge and their nuclei is pushed to one side These cells accumulate fat, they enlarge and their nuclei is pushed to one side When they become too abundant they crowd out other cell types and form “adipose tissue” When they become too abundant they crowd out other cell types and form “adipose tissue” Found: between muscles, around kidneys, behind eyeballs, surface of the heart, and around joints. Found: between muscles, around kidneys, behind eyeballs, surface of the heart, and around joints.

Adipose tissue

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

4. Dense Connective Tissue: tendons and ligaments 4. Dense Connective Tissue: tendons and ligaments Very strong and can withstand pulling forces. Very strong and can withstand pulling forces. Binds body parts together Binds body parts together Has poor blood supply and is very slow to heal. Has poor blood supply and is very slow to heal. This is why sprains, damage to tissue around joints, takes considerable time to heal. This is why sprains, damage to tissue around joints, takes considerable time to heal.

Dense Connective Tissue P.158 P.158

5. Elastic Connective Tissue: found in the attachments between bones of the spinal column. 5. Elastic Connective Tissue: found in the attachments between bones of the spinal column. Very rare in the body but are found in large arteries such as the aorta. Very rare in the body but are found in large arteries such as the aorta. tn_elas_ct.html tn_elas_ct.html tn_elas_ct.html tn_elas_ct.html

6. Cartilage: rigid, provides support, framework, attachments, provides a structural model for many developing bones. 6. Cartilage: rigid, provides support, framework, attachments, provides a structural model for many developing bones. Contains a large volume of water Contains a large volume of water Lacks a direct blood supply, blood vessels surround it, obtain nutrients by diffusion Lacks a direct blood supply, blood vessels surround it, obtain nutrients by diffusion This is why torn cartilage heals so slowly This is why torn cartilage heals so slowly

3 types of cartilage 1. Hyaline: most common, tips of bones at joints, soft part of the nose, supporting rings of the trachea. Prominent in early development. 1. Hyaline: most common, tips of bones at joints, soft part of the nose, supporting rings of the trachea. Prominent in early development. 2. Elastic: more flexible, ears and larynx 2. Elastic: more flexible, ears and larynx 3. Fibrocartilage: very tough, shock absorber, intervertebral discs, knees and pelvis. 3. Fibrocartilage: very tough, shock absorber, intervertebral discs, knees and pelvis.

7. Bone: 7. Bone: Most rigid connective tissue Most rigid connective tissue Internally supports body structures Internally supports body structures Very active tissue Very active tissue Heals much more rapidly than injured cartilage because of close access to a blood supply Heals much more rapidly than injured cartilage because of close access to a blood supply

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