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Epithelial tissues

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Human cell viewed under a light microscope (A) (bio1151.nicerweb.com/class04.html) Human cell viewed under an electron microscope (B) (bio1151.nicerweb.com/class04.html) Compare the cell diagrams you have provided for parts a) and b) and state the differences observed with reference to the components viewed in both illustrations. Large organelles found within cells can be seen under a light microscope such organelles that can be seen are: the cell wall, Mitochondria, nucleus, plasma cell membrane, golgi apparatus and cytoplasm The light microscope however, has limitations in terms of resolution for example because the magnification can only go up to a certain magnification, a number of smaller organelles within a cell cannot be seen as a light microscope is not as strong as an electron microscope where you can get more detailed images due to it having a stronger magnification resolution. Even if a light microscope had greater powers of magnification, not much detail would be seen due to lack of resolution by light rays. Electron microscopy has great power of resolution and can magnify up to 500,000 times therefore resulting in a more detailed and defined outcome. As you can see in diagram A the image is in much simpler version than the one in diagram B.In diagram A you can see the main large organelles which include the mitrochondrion,nucleus,cytoplasm,chromatin,golgi apparatus and nuclear membrane. Diagram B shows many of the same structures that we can see in diagram A but in much more detail for example in diagram A we can only ...read more.


Overall the Epithelial tissue: * provides physical protection; * controls permeability; * provides sensations and * produces specialized secretions Connective tissues There are many types of connective tissue in the body. Generally speaking, connective tissue adds support and structure to the body. Most types of connective tissue contain fibrous strands of the protein collagen that add strength to connective tissue. Some examples of connective tissue include the inner layers of skin, tendons, ligaments, cartilage, bone and fat tissue. In addition to these more recognizable forms of connective tissue, blood is also considered a form of connective tissue. Connective tissues supports and secures other tissues it also stores fat, transport substances, protect against disease, and help repair tissue damage. They occur throughout the body. Connective tissues are characterized by an large quantity of intercellular matrix with relatively few cells. Connective tissue cells are able to reproduce but not as rapidly as epithelial cells. Most connective tissues have a good blood supply but some do not. Unlike epithelial tissue, connective tissue typically has cells scattered throughout an extracellular matrix. The matrix consists of widely spread fibres rooted in a ground substance, which may range in form from solid to liquid. The ground substance functions as a medium through which nutrients can diffuse from blood vessels to nourish the cells. The types of connective tissue include: * Loose connective tissue, * adipose tissue, * dense fibrous connective tissue, * elastic connective tissue, * cartilage, * Osseous tissue (bone), and * Blood. ...read more.


rapid and efficient gas exchange is facilitated by the design of the thin epithelium, lining the lung's airspaces, alveoli, and their associated capillaries. Both Alveolus and capillary are lined by a single layer of flat cells which is an excellent example of simple Squamous Epithelium. Chronic gum disease may affect other health conditions for several reasons, the experts said. Oral bacteria can make their way into the bloodstream, causing inflammation of other body tissues. Oral infections may also trigger inflammatory immune responses, adversely affecting the rest of the body. What are autoimmune diseases? Our bodies have an immune system that protects us from disease and infection. But if you have an autoimmune disease, your immune system attacks itself by mistake, and you can get sick. Autoimmune diseases can affect connective tissue in your body (the tissue which binds together body tissues and organs). Autoimmune disease can affect many parts of your body, like your nerves, muscles, endocrine system (system that directs your body's hormones and other chemicals), and digestive system. The tissues of the body are interdependent. For example, muscle tissue cannot produce movement unless it receives oxygen carried by red blood cells, and new bone tissue cannot be formed unless epithelial tissue absorbs calcium and other nutrients from the digestive tract. Also, all tissues in the body die if cancer or some other disease destroys the tissues of vital organs such as the liver or kidneys. Examples of muscle tissue are contained in the muscles throughout your body. ...read more.

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