What Is Connective Tissue

Connective Tissue

Connective tissue support, protect and bind together other tissue. Connective tissue is the diversity of cells which containing large quantity of extracellular matrix. Tissue-

Classification of connective tissue

1. Loose connective tissue
2. Dense connective tissue
3. Cartilage
4. Bone tissue

Loose connective tissue

Fibers are loosely arranged between the cells in loose connective tissue.

Loose connective tissues are three types:

Areolar connective tissue

It consists of fibers (collagen, elastic and reticular) and several types of cells (Fibroblasts, macrophages, adipocytes, mast cell, plasma cell and other kinds of blood cells). 

Areolar connective tissues are one of the most distributed connective tissue.

Composition: 

Fibers: Collagen, elastic and reticular.

Cells:  Fibroblasts, macrophages, adipocytes, mast cell, plasma cell and other kinds of blood cells.

Location: 

Subcutaneous deep to skin, around blood vessels, nerve.

Function:

Areolar connective tissue provide support, elasticity and strength.

Adipose connective tissue

Adipose tissue composed with fibroblast cells (also known as adipocytes cells) that cells are specialized for storage for fats (triglycerides).

Composition: 

Cells: adipocytes or fibroblast.

 

Location:  

Around the heart kidneys, behind eyeball.

Function:

• Protects and supports body organs.
• Reduces heat loss through skin.
• In new born, Generate heat to maintain normal body temperature. 

Reticular connective tissue

Composition: 

Fiber: reticular fibers

Cells: reticular cells 

Location: 

Spleen, lymph nodes, red bone marrow.

Function: 

• Help to binds smooth muscle tissue (SMT) cells.
• Help to form stroma (shape) organ.  
• Help to remove aged blood cells in spleen.

Dense connective tissue

The fibers arranged between the cells are thick and closely packed. 

Dense connective tissues are three types:

Dense regular connective tissue

Composition:

 
Fibers: mainly collagen fibers are regularly arranged in bundles.  Fibroblast present in rows between bundles.   

Matrix: white and shiny 

Location: 

Form tendons (binds muscle to bone), and some ligament (bind bone to bone).

Function: 

Provide strong attachment between many structure such as ligaments and tendons.

 

Dense irregular connective tissue

Composition: 

 
Fibers: 

Collagen fibers are irregularly arranged in bundles with few fibroblast.

Location:

Fibrous pericardium of heart, heart valve, joint capsule

Function: 

 
Help to pulling strength in many directions.    

Elastic connective tissue

Composition: 

Elastic fibers are arranged with fibroblast.

Location: 

Wall of elastic arteries, lung tissue, bronchial tube.

Function:

• Allow stretching of various organs for example; lung- inhale or exhale. 
• After stretching recoil to original shape of organ.

Cartilage

Hyaline cartilage

Composition: 

Resilient gel,  fine collagen fibers.

 
Location: 

Nose, trachea, at the end of bones and fetal skeleton etc.

Function: 

• Provide surface for support and flexibility. 
• It help for movement at joint, hyaline cartilage present at both end of bone, it reduce the fraction.

Fibrocartilage

Composition: 

Thick collagen fibers and perichondrium absent.

Location: 

Cartilage pad of knee, intervertebral disc.

Function:

• Joining and support structures together.
• Make it strongest type of cartilage.

Elastic cartilage

Composition: 

Elastic fibers and perichondrium present.

Location: 

External ear, epiglottis 

Function: 

 
Help to maintain shape of certain structure of organs of body.

Bone tissue

Composition: 

Consist of haversian system that contain lacunae, lamellae, osteocytes, canaliculi and central canals. 

 Spaces between trabeculae are filled with red bone marrow.

Location: 

Bone tissue make up the various parts of bones.

Functions: 

Protect, support and store many minerals. 

Liquid connective tissue

Blood tissue

Composition: 

Blood plasma, RBCs, WBCs and platelets.

Location: 

Blood vessels and heart chambers.

Function:  

RBCs - Transport oxygen. 

WBCs - Built immune system.

Platelets - Essential for blood clotting.

  

Lymph

Lymph is clear extracellular fluid. Lymph is similar to blood plasma but with less protein.