Without collagen, bones would be brittle and shatter easily. Without mineral crystals, bones would flex and provide little support. Osteocytes , bone cells, are located within lacunae. The histology of transverse tissue from long bone shows a typical arrangement of osteocytes in concentric circles around a central canal Figure 4. Bone is a highly vascularized tissue. Unlike cartilage, bone tissue can recover from injuries in a relatively short time.
Cancellous bone looks like a sponge under the microscope and contains empty spaces between trabeculae, or arches of bone proper. It is lighter than compact bone and found in the interior of some bones and at the end of long bones. Compact bone is solid and has greater structural strength.
Blood is a fluid connective tissues. Blood has two components: cells and fluid matrix Figure 4. Erythrocytes, red blood cells, transport oxygen and some carbon dioxide. Leukocytes, white blood cells, are responsible for defending against potentially harmful microorganisms or molecules.
Platelets are cell fragments involved in blood clotting. Some white blood cells have the ability to cross the endothelial layer that lines blood vessels and enter adjacent tissues. Nutrients, salts, and wastes are dissolved in the liquid matrix called plasma and transported through the body.
Lymph contains a liquid matrix and white blood cells. Lymphatic capillaries are extremely permeable, allowing larger molecules and excess fluid from interstitial spaces to enter the lymphatic vessels. Lymph drains into blood vessels, delivering molecules to the blood that could not otherwise directly enter the bloodstream. In this way, specialized lymphatic capillaries transport absorbed fats away from the intestine and deliver these molecules to the blood. Visit this link to test your connective tissue knowledge with this question quiz.
Can you name the 10 tissue types shown in the histology slides? Skip to main content. Chapter 4: The Tissue Level of Organization. Search for:. Connective Tissue Learning Objectives Identify and distinguish between the types of connective tissue: loose, dense, cartilage, bone, and blood Explain the functions of connective tissues. Functions of Connective Tissues. Collagen fibers are fibrous proteins and are secreted into the extracellular space and they provide high tensile strength to the matrix.
Elastic fibers are long, thin fibers that form branching network in the extracellular matrix. They help the connective tissue to stretch and recoil. Reticular fibers are short, fine collagenous fibers that can branch extensively to form a delicate network. Connective tissues encompass a diverse array of tissue types that are involved in binding and supporting body structure and tissues. Connective tissue proper has two subclasses: loose and dense.
Loose connective tissue is divided into 1 areolar, 2 adipose, 3 reticular. Dense connective tissue is divided into 1 dense regular, 2 dense irregular, 3 elastic. These tissues are widely distributed and serve as a universal packing material between other tissues. The functions of areolar connective tissue include the support and binding of other tissues.
It also helps in defending against infection. When a body region is inflamed, the areolar tissue in the area soaks up the excess fluid as a sponge and the affected area swells and becomes puffy, a condition called edema. Adipose tissue : Yellow adipose tissue in paraffin section with lipids washed out. This is loose connective tissue composed of adipocytes. Its main role is to store energy in the form of lipids, although it also cushions and insulates the body.
Adipose tissue is found in specific locations, referred to as adipose depots. This tissue resembles areolar connective tissue, but the only fibers in its matrix are the reticular fibers, which form a delicate network. The reticular tissue is limited to certain sites in the body, such as internal frameworks that can support lymph nodes, spleen, and bone marrow.
This consists of closely packed bundles of collagen fibers running in the same direction. These collagen fibers are slightly wavy and can stretch a little bit. With the tensile strength of collagen, this tissue forms tendons, aponeurosis and ligaments.
This tissue forms the fascia, which is a fibrous membrane that wraps around the muscles, blood vessels, and nerves. Variations in the composition of the extracellular matrix, determines the properties of the connective tissue.
For example, if the matrix is calcified, it can form bone or teeth. Specialised forms of extracellular matrix also makes up tendons , cartilage , and the cornea of the eye.
General connective tissue is either loose, or dense, depending on the arrangement of the fibres. The cells sit in a matrix made up of glycoproteins, fibrous proteins and glycosoaminoglycans , which have been secreted by the fibroblasts, and the major component of the matrix, is in fact, water.
Cells are the predominant feature in tissues specialised for protection haemopoietic tissue, blood - white blood cells or metabolic maintenance adipocytes, blood - red blood cells. This is an example of loose connective tissue from a lymph gland. It contains some cells called 'plasma cells', finer elastin fibres and thicker collagen fibres. Humans are diploid creatures.
This means that for every chromosome in the body, there is another one to match it. Humans are capable of only one mode of reproduction, i. Haploid sex cells gametes are produced.. Lymphocytes are a type of white blood cell capable of producing a specific immune response to unique antigens.
In thi.. The hominid family diversified from the apes around 6 to 8 million years ago. Since then, the evolutionary path has prov.. Neurons generate electric signals that they pass along to the other neurons or target tissues.
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