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| Connective Tissue Proper |
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| It is type of connective tissue in which the matrix is soft and homogenous and encloses cells and fibres. It is also known as binding tissue or loose connective tissue. |
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| Areolar tissue |
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| Areolar tissue is the most common and the most widely distributed type of connective tissue. It has a soft, homogeneous matrix in which both fibres and cells are embedded. The fibres in the matrix are of two types-white and yellow fibres. |
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| The cells present in the matrix are of four types: |
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 Fibrocytes are stellate or star shaped cells, which produce the matrix and white and yellow fibres. |
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 Macrophages are irregular, amoeboid cells which can ingest bacteria and other disease producing germs by phagocytosis. |
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 Mast cells are spherical or oval cells, which produce the anticoagulant heparin. |
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 Fat cells are spherical or oval vacuolated cells, which occur in groups. These cells also called adipocytes, are mainly meant for storage of reserve food (fat) and thermoregulation. |
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| Areolar tissue is widely distributed in the body. It is found forming the protective covering around almost all the visceral organs (e.g. Pericardium of heart, meninges of brain etc.). It also occurs as a packing tissue, loosely filling the unused spaces in the body. It forms a bedding substance called stroma inside many visceral organs like liver and pancreas. It is also found in the blood vessels. It also forms a layer immediately below the skin. |
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| fig. 5.61 Areolar Tissue |
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| Fibrous tissue |
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| Fibrous tissue is a modification of the areolar tissue in which the matrix predominantly contains white fibres. Yellow fibres are reduced. Hence, the tissue becomes rigid and is known for its tensile strength. The fibrous tissue forms structures called tendons, which connect muscles to the bones. |
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| fig.5.62 White Fibrous Tissue |
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| Elastic tissue |
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| Elastic tissue is also a modification of the areolar tissue in which the matrix predominantly contains yellow fibres. Hence, the tissue attains more of flexibility. Elastic tissue forms structure known as ligament, which attach bones to bones. |
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| fig. 5.63 Yellow Elastic Tissue |
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| Adipose tissue |
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| Adipose tissue is another modification of the areolar tissue in which the matrix is characterized by the presence of more of vacuolated fat cells. Other types of cells and fibres are reduced. Adipose tissue is mainly meant for storage of reserve food. It also forms an insulation against loss of heat from the body (e.g. blubber of whale). |
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| fig. 5.64 Adipose Tissue |
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