Transcript Anatomy & Physiology Chapter 3 – Part 3

Anatomy & Physiology
Chapter 3 – Part 3
Tissues
Body Tissues
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Tissues
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Groups of cells with similar structure and
function
4 primary types:
Epithelium
 Connective
 Nervous
 Muscle
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Epithelial Tissues
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Found in different areas:
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Body Coverings
Body Linings
Glandular Tissue
Functions:
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Protection
Absorption
Filtration
Secretion
Epithelial Tissues
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Epithelium Characteristics:
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Cells fit closely together
Have no blood supply of their own
Classification of Epithelium
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Number of Cell
Layers:
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Simple = one layer
Stratified = more than
one layer
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Shape of Cells:
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Squamous = flattened
Cuboidal = cube
shaped
Columnar = column
like
Classification of Epithelium
Connective Tissue
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Includes the most abundant tissues
Functions:
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Binds body tissues together
Supports the body
Provides protection
Connective Tissue
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Extracellular Matrix:
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Non-living material that surrounds living cells
Two main elements:
Ground substance = mostly water along with
proteins and polysaccharides
 Fibers
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Muscle Tissue
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Function is to produce movement
Three types:
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Skeletal Muscle
Cardiac Muscle
Smooth Muscle
Nervous Tissue
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Comprised of
neurons and nerve
support cells
Function is to send
impulses to other
areas of the body
Tissue Repair
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Regeneration
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Replacement of destroyed tissue by the same
kind of cells
Fibrosis
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Repair by dense fibrous connective tissue
(scar tissue)
Events in Tissue Repair
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Capillaries become very permeable
Regeneration of surface epithelium
Regeneration of Tissues
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Tissues that regenerate easily:
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Tissues that regenerate poorly:
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Epithelial
Fibrous Connective
Bone
Skeletal Muscle
Tissues that are replace largely with scar tissue:
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Cardiac Muscle
Nervous tissue within the brain and spinal cord
Developmental Aspects of
Tissues
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With old age there is a decrease in mass
and viability in most tissues.
Developmental Aspects of
Tissues
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Some cells lose their ability to divide when they
are fully mature.
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This is called AMITOTIC
For example: heart muscle and nervous tissue
However, if these tissues are injured, the lost cells
cannot be replaced by the same type of cells but by
scar tissue.
If a cell multiplies wildly, the abnormal cell mass
is known as NEOPLASM.
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May be benign or malignant (cancerous)
Simple Epithelium
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Simple Squamous
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Single layer of flat
cells
Lines body cavities
Lines lungs and
capillaries
Simple Epithelium
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Simple Cuboidal
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Single layer of cubelike cells
Covers the ovaries
Simple Epithelium
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Simple Columnar
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Single layer of tall
cells
Includes GOBLET
CELLS – produce
mucus for secretion
Lines the digestive
tract
Simple Epithelium
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Pseudostratified
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Single layer, but some
cells are shorter than
others
Found in the
respiratory tract – has
cilia
Functions in
absorption and
secretion
Stratified Epithelium
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Stratified Squamous
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Several layers of flat
cells
Locations:
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Skin
Mouth
Esophagus
Stratified Epithelium
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Transitional Epithelium
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Shape of cells depends
upon the amount of
stretching
Lines organs of the
urinary system to help
stretch the bladder
Glandular Epithelium
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Gland = one or more cells that secretes a
particular product
Two major gland types:
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Endocrine Glands
Ductless
 Secretions hormones directly into the blood
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Exocrine Glands
Have ducts
 Include sweat and oil glands
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Connective Tissue Types
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Dense Connective
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Made up of collagen
fibers
Examples: tendons
and ligaments
Connective Tissue Types
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Adipose
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Made of areolar tissue
with fat globules
Functions:
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Insulates the body
Protects organs
Serves as a site of fuel
storage
Connective Tissue Types
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Areolar
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Most widely distributed
connective tissue
Soft tissue
Contains all fiber types
Connective Tissue Types
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Hyaline Cartilage
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Most common
cartilage
Entire fetal skeleton is
hyaline cartilage
Connective Tissue Types
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Elastic Cartilage
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Made of elastic fibers
Provides elasticity
Example: supports the external ear
Connective Tissue Types
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Fibrocartilage
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Highly compressible
Example: forms
cushion-like discs
between vertebrae
Connective Tissue Types
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Bone
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Composed of a hard
matrix of calcium salts
Used to protect and
support the body
Connective Tissue Types
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Blood
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Blood cells are
surrounded by fluid
matrix
Functions as the
transport vehicle for
materials
Connective Tissue Types
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Reticular
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Delicate network of
interwoven fibers
Forms internal support
for the lymph nodes,
spleen, and bone
marrow
Muscle Tissue Types
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Skeletal Muscle
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Can be controlled
voluntarily
Cells are striated
Cells have more than
one nucleus
Attached to the bones
Function: Movement
Muscle Tissue Types
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Smooth Muscle
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Involuntary muscle
Surrounds hollow
organs
No visible striations
One nucleus per cell
Function: movement
Muscle Tissue Types
Cardiac Muscle
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Found ONLY in the
HEART
Cells are striated
One nucleus per cell
Function: pump blood