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Chapter 5: Tissue
Types of Tissues
• A tissue is composed of specialized
cells that perform a function in the
body.
• The human body has four major types
of tissues:
The 4 types are:
1. Epithelial
2. Connective
3. Muscle
4. Nervous
Some Cancers that occur in
tissue are:
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Carcinomas – cancers of epithelial tissue
Sarcomas – cancers of connective tissue
Leukemia – cancer of blood
Lymphomas – cancers of lymphatic tissue
1. Epithelial Tissue
Characteristics of epithelial tissue:
• Epithelial tissue is made of highly
packed cells that line the body surface and
inner body cavities.
• Epithelial tissue functions in protection,
secretion, absorption, excretion, and
filtration.
Obj. #1: Describe the types of
Epithelial Tissue
1. Simple Squamous epithelium
• a single layer of of flattened cells
• is found lining the lungs and blood
vessels.
• Allows substances to pass into and out
of tissue…when oxygen enters blood
stream
Simple squamous epithelium
These flatten cells allow
diffusion
into and out of the cell.
2. Cuboidal epithelium
• contains cube-shaped cells
• is found lining the kidney tubules and
glands
• functions to store secretions
Simple Cuboidal Ttissue
3. Simple Columnar epithelium
• has elongated cells with nuclei at the bottom of
cells
• is found in the digestive tract.
• secretes digestive fluid
• absorbs nutrients
• cells have microvilli on ends to increase
absoption
• has goblet cells that make mucus
Simple Columnar
Epithelial
4. Pseudostratified Columnar epithelial• Long cells with cilia on end
• Lines respiratory tract and reproductive
tract
• Promotes movement of mucus in
repiratory tract
• Promotes movement of egg in oviducts
Pseudostratified ciliated columnar
epithelium
5.
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Stratified Squamous
Found in outer skin and lines the mouth
Occurs in layers- stacks of flatten cells
Oldest layer is on top…youngest on
bottom
Protects body from invasion
Outer layer sloughs off as cells die
Stratified Squamous Epithelium
• Topmost layer is
dead cells
• They flatten out and
form a protective
layer
• Skin
6. Transitional epithelial tissue
• Stretches
• Found in bladder
Transitional Epithelial
Obj. #2 Describe Connective Tissue
Characteristics:
• binds organs together, provides
support and protection, fills spaces,
produces blood cells, and stores fat.
• matrix material is the material that fills the
cell. It is a semifluid or solid.
• Different types of fibers float in matrix
Types of Connective Tissue
.
1. Loose fibrous-supports epithelium and
many internal organs.
• Wrinkles form when loose fibrous tissue
ages.
• Sun exposure cause fibers in loose to
break much like a rubber band breaks..
this leads to wrinkles forming
Loose fibrous connective tissue
2. Dense fibrous-is found in tendons and
ligaments.
• Very tightly packed cells
• Has very little blood supply..so when a
person injures a ligament or tendon…it will
take a long time to heal
Dense Connective Tissue
3.Adipose tissue is found beneath the
skin and around certain internal
organs.
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Functions:
Cushions
Insulates
Stores energy-cells look
empty…but contain fat droplets
Adipose (fat) Connective
Tissue
• Lipid (fat) droplet
• nucleus
• collagen fibers
4. Cartilage
Cartilage found in outer ear, nose, and
between bones.
Function:
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Flexible
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Protects
Cartilage
5. Bone
• Bone is the most rigid connective tissue
with its matrix of calcium and other
inorganic salts and protein fibers.
• Compact bone makes up the shafts of
long bones and consists of ring-linke
circels called osteons which contain blood
vessels and nerves.
Compact bone
6. Blood
• Blood is a fluid connective tissue
containing blood cells in liquid plasma.
• Blood has many functions:
• Keeps body chemistry within limits
• Transports nutrients and wastes to cells
• Distributes heat
Blood, a fluid tissue
Formed elements of blood
Obj. #3 Describe Muscle Tissue
There are 3 types
1. Skeletal muscle, under voluntary
control, is attached by tendons to
bones and allows for movement.
- have striations which are bands of
fibers
Skeletal muscle
2. Smooth (visceral) muscle is involuntary and
nonstriated.
• Long, tapered cells,
• Smooth muscle is found in walls of organs.
• Smooth muscle contracts more slowly than
skeletal muscle but can remained contracted
for a longer period.
Smooth muscle
3. Cardiac muscle is found only in the walls
of the heart and functions to pump blood.
• Cardiac muscle has striations but is
involuntary.
• Cardiac muscle fibers are branched and
have a single nucleus.
Cardiac muscle
4. Nervous Tissue
• Nervous tissue found in the brain and
spinal cord is made up of cells called
neurons.
• Neurons have three parts:
• Dendrites – carry impulses to the neuron
• Cell body – houses nucleus
• Axon – carries impulse away from cell
Nerve Tissue
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Neuron
process
nucleus
nucleolus
Neuroglia
A neuron and some types of
neuroglia