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Ch 4: Types of Connective tissue

Descriptive HistologyCLS 222 Saida Almashharawi

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To know the classification of connective tissue& it is categories

Objectives

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There are two main sub-classes of connective tissue :-

1) Connective tissue proper

2) Specialized connective tissue.

Classification of connective tissue

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Connective tissue proper is subdivided further into Loose (or sometimes referred to as areolar) Dense: this is subdivided to

o Regular

o Irregular

Connective tissue proper

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Specialized connective tissue is further subdivided into :Adipose connective tissueReticular connective tissueElastic connective tissueCartilage Supportive connective tissueBoneBlood Fluid connective tissuelymph

Classification of connective tissue

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1.Loose connective tissue

is characterized by small interwoven collagen fibers embedded in more ground substance than in dense connective tissue.

Fewer and smaller collagen fibers compared with dense connective tissue.

The fibroblast is the main cell that produces and maintains the ground substance and collagen fibers.

Connective tissue proper

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Loose connective tissue

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Location:

1) Around small blood and lymphatic vessels

2) Fills the spaces between muscle and nerve fibers.

3) Mucous membranes

4) Glands

Loose connective tissue

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Structure: Has all the main components of connective tissue (cells, fibers, and ground substance) Cells:

1) Fibroblasts

2) Macrophages,

3) Other types of connective tissue cells are also

present.

Loose connective tissue

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Fibers:1) Collagen

2) Elastic

3) Reticular

Ground substances:4) Flexible

5) Well vascularized

6) Not very resistant to stress.

Loose connective tissue

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2.Dense connective tissue

1) It has the same components found in loose

connective tissue, but there are fewer cells& more

fibers

2) Dense connective tissue is less flexible and more

resistant to stress than loose connective tissue.

Connective tissue proper

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2.Dense connective tissue

Regular Irregular

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1. collagen fibers are arranged in bundles

2. collagen fibers form a 3-dimensional network

providing resistance to stress from all directions.

Dense irregular connective tissue

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LOCATION:• Deep fascia (thin sheath of fibrous tissue

enclosing a muscle or other organ)

• Dermis of skin

• Joint capsules

• Heart valves

Dense irregular connective tissue

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Dense irregular connective tissue

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1. The collagen bundles of dense regular connective tissue are arranged according to a definite pattern,

2. This arrangement offers great resistance to traction forces.

Location: forms tendons & ligaments

Dense regular connective tissue

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Dense regular connective tissue

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Consists of reticular fibers and reticular cellReticular fibers are very small, on the order of 1

micron in diameter. They are made up of type III collagen (collagen

fibers are made up of type I collagen).Reticular fibers cannot be visualized in specimens

stained with Hematoxylin-Eosin mainly because they are so small and contain so little collagen protein.Found in :

• Liver• spleen • lymph nodes

Reticular connective tissue

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Reticular tissue

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consists of :Adipocytes; appearing fat cells.

Function :

1. protects and insulates the

organs

2. serves as an energy reserve

Adipose tissue

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Adipose tissue

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LOCATION

• Hypodermis

• Around the Kidneys& Eyeballs

• Female breasts

• Abdominal region

Adipose tissue

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adipose tissue represents 15–20% of the body weight

in men of normal weight

in women of normal weight, 20–25% of body weight.

Adipose tissue

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composed of:• Branching elastic fibers

• Network of collagen fibers

• Fibroblasts Location:

• Dermis

• Lungs

• Blood vessels

Elastic tissue

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Elastic tissue

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What kind of tissue does this represent?

Loose (areolar) connective tissue

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What kind of tissue does this represent?

Where in the body can you find this tissue?

Adipose tissue

fat

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What kind of tissue does this represent?

Where in the body can you find this tissue?

Dense connective tissue

tendons; ligaments

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