Tissues
Alice Christopher
Unit 5

Tissues
A tissue is made up of cells that have the exact function.
The human body contains four basic types of tissue contributing to homeostasis by providing diverse functions including protection, support, communication and resistance to disease. The four main types are epithelial, connective, muscle and nerve.

Epithelial Tissue
There are two types: Simple Epithelial tissue and Compound Epithelial tissue.
These are the tissues that covers the body’s surfaces and lines hollow organs, body cavities and ducts. As well as forming glands.
Simple Epithelial tissue is a single layer of cells. These cells are involved in the movement of substances and production. It releases and absorbs substances. This is shown when the simple epithelial tissue changes its shape.
Compound tissue however is two or more layers of cells. It is the protection of the underlying tissue in many parts of the body.
Cuboidal Epithelium

Ciliated Columnar Epithelium Squamous Epithelium

Simple Epithelial Tissue
• There are four different types of cells in the Simple epithelial tissue: cuboidal cells, columnar cells, squamous cells and ciliated cells.
• Cuboidal cells: This cell may have microvilli, which is a microscopic finger-like projection which increases the surface area. Also, the cell is responsible for secretion and absorption.
These cells are found within the body. An example of this is; the surface of the ovary and many small ducts of glands such as the pancreas.
• Squamous cells: These cells are flat, this is because it allows rapid movement of substances through them. These cells are found within the body. An example of a squamous cell would be; blood vessels and lining the heart.
• Ciliated cells: these are the same as cuboidal cells but with cilia (or hairs) which take part in the movement of substances and secretion through the tissue. These cells are found within the body. An example of a ciliated cell is; inside the upper respiratory tract where it assists the movement of mucus. Also another example could be involved the movement of the egg cell from the fallopian tubes to the uterus.
• Columnar cells: This cell may have cilia or microvilli, which is specialised for secretion and absorption. These cells are found within the body. An example of this cell is: the lining of the digestive tract.

Compound Epithelial Tissue
Compound tissue however is two or more layers of cells. It is the protection of the underlying tissue in many parts of the body where it is considerable to wear or tear. The cells are known to be quite simple. The cells may be keratinised.
Keratin, this is a tough fibrous protein that helps in protecting the skin. Also, the underlying tissue is protected from heat, microbes that cause infections, diseases and chemicals. Epithelial tissue can be found in the lining of the urinary tract and the keratinised cells form the skins outer layer.

Connective tissue
There are many different types of connective tissues: Blood, cartilage, bone, areolar tissue, adipose tissue.
This is known as one of the most widely distributed tissue in the body. It consists of cells and matrix. The matrix fills each of the spaces between cells and it consists of protein based fibres that are secreted by the connective tissue cells. These cells may be very hard or flexible, but very firm. This tissue binds, supports and strengthens many other body tissues. Protection and insulation are provided in to internal organs in the body as well as separating structures such as the skeletons muscles. Connective tissues are known to have a plentiful blood supply as well as nerve endings.

Blood
This is a fluid connective tissue. Its function is transporting blood through the body (major transport system). Blood is made of many different blood cells, such as:
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Red blood cells
White blood cells
Platelets
Plasma

Cartilage
This is different to other connective tissues. This is because it doesn’t contain blood and it has