Epithelial,Connective,Muscle and Nervous
Tissues
General Epithelial Tissues
1. They are found throughout the body: covering organs, forming inner linings of body cavities .
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1. They are anchored to Connective Tissues by the basement membrane.
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1. They lack blood vessels.
○ IF they do not have blood vessels how do you think they receive nutrients?
General Epithelial Tissues1. They divide
rapidly. ○
1. They are tightly packed together.
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1. They are classified according to their layers of cells.
General Epithelial Tissues○ How do you think the characteristics
we just listed relate to what epithelial tissues do?
○ They divide rapidly- how does that help the body?
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○ Injuries can heal rapidly
to these tissues, skin and
stomach cells are continually
damaged and replaced
quickly.
General Epithelial Tissues
•They are tightly packed- how does this help the cell?
•They form protective barriers in places like the outer skin, and your mouth.
○ Simple: composed of a single layer of cells.
○ Stratified: those with two or more layers of cells.
○ Squamous: Flattened cells. ○ Cuboidal: Those with cubed shaped cells. ○ Columnar: Elongated cells.
TYPES OF EPITHELIAL CELLS: Classified by layers
1. Simple Squamous Epithelium○
What is Simple Squamous Epithelium?
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○ Where would you find it?○
○ What is its function?○
TYPES OF EPITHELIAL CELLS: Classified by layers
Simple Squamous Epithelium○ What is Simple Squamous Epithelium?
○ Thin (One layer), flattened cells○ Fit tightly together with flat nuclei○ Substances pass through easily by
diffusion○ Where would you find it?
○ Lines the lungs where O2 and CO2 are exchanged.
○ Lines the walls of capillaries, blood and lymph vessels.
○ What is its function? ○ Helps gases exchange and other
chemicals.
Simple Squamous Epithelium
2. Simple Cuboidal Epithelium
○ What is Simple Cuboidal Epithelium?
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○ Where would you find it?
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○ What is its function?○
Simple Cubodial Epithelium○ What is Simple Cuboidal Epithelium?
○ Single layer of cells○ Cubed shaped cells with a central
nucleus. ○ Where would you find it?
○ Covers the ovaries. ○ Lines the kidneys and ducts of certain
glands such as: salivary glands, thyroid, pancreas and liver.
○ What is its function? ○ Functions in secretion and absorption.
Simple Cuboidal Epithelial
Simple Columnar Epithelium
○ What is Simple Columnar Epithelium?
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○ Where would you find it?○
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○ What is its function?
Simple Columnar Epithelium○ What is Simple Columnar Epithelium?
○ Elongated cells (longer than they are wide)○ Single layer of cells. ○ Nucleus near the basement membrane○ Can have cilia that help in movement
○ Where would you find it?○ Lines the uterus (help move eggs to uterus). ○ Lines the organs of the digestive tract
○ What is its function? ○ Thick tissues to protect.○ Secretes digestive fluids and absorbs
nutrients from digested food.
Simple Columnar Epithelium
Pseudostratified Columnar Epithelium
○ What is Pseudostratified Columnar Epithelium?
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○ Where would you find it?
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○ What is its function?○
○ What is Pseudostratified Columnar Epithelium?○ Elongated cells (longer than they are wide)○ Appears to have more than one layer but does
not. ○ Nucleus is located at different ends which gives
it the layer look. ○ Have cilia
○ Where would you find it?○ Lines the passage of the respiratory system.
○ What is its function? ○ Sticky to trap dust and microorganisms that
enter with air. The cilia move the captured particles up and out of the airways.
○ Goblet cells secrete mucus to help move dust.
Pseudostratified Columnar Epithelium
Stratified Squamous Epithelium
○ What is Stratified Squamous Epithelium?
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○ Where would you find it?
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○ What is its function?○
Stratified Squamous Epithelium○ What is Stratified Squamous Epithelium?
○ Lots of layers of the cell. ○ Flattened because cells divide and push the
older ones outward where they are flattened. ○ Where would you find it?
○ Forms the outer layer of the skin (your epidermis)
○ Soft tissue part forms in the vagina○ What is its function?
○ They produce keratin a protein that produces a dry, tough, protective material that prevents water and other substances from entering or leaving.
○ Protects and lines the vagina without keratin.
Stratified Squamous Epithelium
Stratified Cuboidal Epithelium
○ What is Stratified Cuboidal Epithelium?
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○ Where would you find it?
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○ What is its function?○
Stratified Cuboidal Epithelium
○ What is Stratified Cuboidal Epithelium?○ 2 or 3 layers of cuboidal cells.
○ Where would you find it?○ Lines the lumen○ Lines the glands: mammary glands, sweat
glands, salivary glands, and pancreas. ○ What is its function?
○ Gives more protection than a single layer does.
Stratified Cuboidal Epithelium
Stratified Columnar Epithelium
○ What is Stratified Columnar Epithelium?
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○ Where would you find it?
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○ What is its function?○
Stratified Columnar Epithelium
○ What is Stratified Columnar Epithelium?○ Several layers of columnar cells. ○ Superficial layer of columnar cells next to
layers of cuboidal cells. ○ Where would you find it?
○ Male reproductive organs○ What is its function?
○ Allows the organ to contract and stretch.
Stratified Columnar Epithelium
Transitional Epithelium
○ What is Transitional Epithelium?
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○ Where would you find it?○
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○ What is its function?○
Transitional Epithelium○ What is Transitional Epithelium?
○ Specialized type of epithelium cells○ Can be stretched or unstretched (ovals)
○ Where would you find it?○ The liner of the bladder, uterus and urethra.
○ What is its function? ○ They can change because of increased
tension. ○ So they help organs expand- bladder when it
is full then returns to normal.○ Stops urine from going back into the system.
Transitional Epithelium Unstretched
Transitional Epithelium
Glands○ Specialized cells that that secrete
substances into ducts or body fluid. ○ Found in Columnar cells or cuboidal. ○ Two types: exocrine glands and
endocrine glands. ○
○ Exocrine- secretes product into an internal or external duct or tube that travels to other organs or glands.
○ Endocrine- Glands that secrete product into tissues or blood direction.
Glands
The 8 Connective Tissues
○ 1. Loose Connective Tissue○ 2. Adipose Tissue (fat tissue)○ 3. Dense Connective Tissue○ 4. Blood○ 5. Bone○ 6. Hyaline Cartilage○ 7. Fibrocartilage○ 8. Elastic Cartilage
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General Characteristics of Connective Tissues
○ Binds structures○ Provides support and
protection○ Fill spaces○ Stores fat○ Produce blood cells○ Protect against infections○ Help repair tissue damage
General Functions of Connective Tissues
○ They divide easily. ○ Have a large blood supply and are
well nourished. (this is where epithelial cells receive blood and nutrients).
○ Connected to epithelial cells below the basement membrane.
○ Some have a fixed number of cells and some are temporary and appear when needed in response to injury or infection.
Loose Connective Tissue- Areolar tissue
Loose Connective Tissue- Areolar tissue○ What is Loose Connective tissue?
○ Tissue that forms delicate thin membranes throughout the body.
○ Where would you find it?○ Underneath epithelial cells to nourish
them.○ Fills the spaces between skin and organs or muscles.
Loose Connective Tissue- Areolar tissue○ What is it’s
function?○ Binds organs
together○ Holds tissue fluids○ Protects, insulates
and stores fat
Adipose Tissue
Adipose Tissue○ What is Adipose tissue?
○ Fat○ When cells store fat in droplets within
their cytoplasm and enlarge.
○ Where would you find it?○ Beneath skin, around kidneys or
organs, on surface of the heart. ○ Around the eyeballs and certain joints
as well as spaces between muscle.
Adipose Tissue○ What is its function?
○ Cushions joints and some organs○ Insulates beneath the skin○ Stores energy○ When adipose cells become too
numerous the crowd the cell and other cells forming fat tissue.
Dense Connective Tissue
Dense Connective Tissue○ What is Dense Connective tissue?
○ Closely packed thick collagenous fibers and elastic fibers.
○ Very strong to withstand pulling forces.
○ Where would you find it?○ Ligaments and tendons○ The white part of your eye. ○ Deep skin layers
Dense Connective Tissue○ What is it’s function?
○ Binds body parts together through tendons (muscle to bone) or ligaments (bone to bone)
○ Protects the eye○ Blood supply is poor so tissue repair is
poor.
How many of you have ever torn a ligament or tendon? These dense tissues are why it takes so long to recover!
Specialized Connective Tissues:
1. Blood
○ What is Blood Tissue?○ Red blood cells, white blood cells and platelets that are in a fluid of plasma. Where would you find
it?○ Formed in the red
marrow within the hollow parts of certain long bones
Blood
○ What is the function?○Transports materials between body cells○Helps maintain stable internal homeostasis.
Bone
○ What is Bone Tissue?○ Rigid and hard tissue
formed by minerals such as Calcium
Where would you find it?
○ The skeletal system throughout your body!
Bone
Bone○ What is the function?○ Internally supports the body structure○ Attachment for muscles○ Protects cranial organs and thoracic
organs○ Contains and produces red blood cells as
well as calcium and phosphorus○ Heals more rapidly than cartilage
Cartilage General Characteristics○ Three types:
○ Hayline Cartilage○ Elastic Cartilage○ Fibrocartilage
○ Rigid Connective Tissue○ Provides support○ Protects○ Lack a direct blood supply, get minimal
blood by diffusion but not enough- so healing to cartilage is slow.
Elastic Cartilage
Elastic Cartilage
○Functions and location:○Very elastic and flexible○External ears and parts of the larynx
Fibrocartilage
Fibrocartilage○ A very tough tissue
○ A shock absorber for structures that are subjected to pressure.
○ Example: cushions bones in the knees and between vertebrates in the spinal column.
Hyaline Cartilage
Hyaline Cartilage○ Most common○ Important in the growth of bones○ Found in the ends of bone, joints,
the soft part of the nose, and respiratory passage
Muscle Tissues○ Characteristics: ○They are contractile- the
elongated cells can shorten and lengthen.
○As the contract, muscle fibers pull at the attached end causing body parts to move.
○Three types of muscle tissues: ○1. Skeletal Muscle tissue○2. Smooth Muscle tissue○3. Cardiac Muscle tissue
Cardiac Muscle
○ What is Cardiac Muscle?
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○ Where would you find it?
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○ What is its function?
Cardiac Muscle
○ What is it? ○ Cells are striated and○ joined end to end.○ One nuclei
○ Where do you find it?○ Only in the heart
○ What is it’s function? ○ Involuntary (works without you knowing or
thinking)○ Pumps blood through the heart chambers
and into blood vessels. ○ Internal volume can change as it pumps
blood and contracts
Cardiac Muscle
Skeletal Muscle
○ What is Skeletal Muscle?
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○ Where would you find it?
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○ What is its function?
Skeletal Muscle○ What is it?
○ Voluntary muscle (controlled by conscious effort)
○ Lots of nuclei in each cell
○ Has striations○ Where is it?
○ Found in muscles that attach bone.
○ What is its function?○ Nerves stimulate the muscle fiber to
contract and relax○ This helps us move our head, trunk,
and limbs. ○ Enable us to make facial expressions,
write, talk, sing, chew, breath and so forth!
○ Basically concerned with whole body movement
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Skeletal Muscle
Skeletal Muscle
Smooth Muscle
○ What is Smooth Muscle?
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○ Where would you find it?
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○ What is its function?
Smooth Muscle○ What is it?
○ No striations○ Short and spindle shaped, with single
central nucleus○ Involuntary actions
○ Where is it? ○ The walls of organs (stomach, intestine, bladder, blood vessels)○ Internal volume canChange to contract
Nervous tissue
○ What is Nervous tissue?
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○ Where would you find it?
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○ What is its function?
Nervous Tissue
○ What is it? ○ Made up of cells of neurons- which
sense changes in their surroundings○ Where is it?
○ The brain, spinal cord and peripheral nerves.
Nervous Tissue○ What is the function?○Transmit nerve impulses to other
neurons, muscles or glands. ○They communicate with other
cells and muscles and tell body functions what to do.