Tissues Flashcards
What is a tissue?
A tissue is a collection of similar cells with a common origin that work together to perform a specific function.
What are the 4 types of tissue found in the human body?
The 4 types of tissue are: Epithelial Tissue, Nervous Tissue, Connective Tissue, and Muscle Tissue.
What are the two types of Epithelial tissue?
The two types of Epithelial tissue are: Simple and Compound.
What is Simple Epithelial tissue?
Simple Epithelial tissue consists of a single layer of cells that lie on a basement membrane. It is found in in areas where absorption of substances occurs (E.g., Lining of alveoli of the lungs).
What is Compound Epithelial tissue?
Compound Epithelial tissue has more than one layer of cells, with the lower layer lying on a basement membrane. Compound Epithelia are present on surfaces which need to be protected, such as the skin.
What is Simple Squamous Epithelial tissue?
Squamous Epithelial cells are very flat with each nucleus forming a lump in the centre. They fit together closely and their function is too allow materials to pass through via diffusion and osmosis.
Where is Simple Squamous Epithelial tissue found?
It is found in the Lung alveoli, and the Lining of blood capillaries, and the inner lining of arteries and veins.
What is Simple Cuboidal Epithelial tissue?
Simple Cuboidal Epithelial tissue has cube-shaped cuboidal epithelial cells, with spherical nuclei. They often line ducts and tubes and can allow materials to pass through in a similiar way to squamous epithelia. They often occur in glandular tissues making secretions.
Where is Simple Cuboidal Epithelium found?
Simple Cuboidal Epethelium is found in Kidney tubules, sqeat ducts, and glands such as the thyroid gland and breast tissue.
What is Simple Columnar Epithelial tissue?
Columnar Epithelial cells are tall cells (Like a column), with slightly oval nuclei. They can often be associated with microscopic filaments known as cilia and are called ciliated epithelia. A ciliated cell has a larger surface area than a non-ciliated cell, this increases the rate of diffusion of substances into the cell.
Where is Simple Columnar Epithelial tissue found?
Simple Columnar Epithelial tissue is found in the Trachea and bronchi (Respiratory tract - diffusion of gases), and the Villi in the small instestine (Diffusion of ‘food’ molecules- E.g., Glucose, amino acids, and triglycerides).
What is Compound Epithelial tissue?
Compound epithelia protects structures, there is either simple or keratinised compound epithelium. Simple Compound epithelium has several layers of cells (Stomach lining)., and keratinised Compound epithelium has several layers of cells (Skin). Keratin is a tough protein.
What is non-keratinised Compound Epithelial tissue?
The lowest layer of cells on the basement membrane actively divides and the older cells are pushed upwards. This type of epithelia is usually a pink colour (Due to good blood supply) and oftten forms the ‘mucous membrane’.
Where is Compound epithelial tissue found?
The vagina, mouth, tongue, and oesophogus are lined by stratified epithelia consisting of layers of squamous, cuboidal, or columnal cells, which gradually become flattened by pressure from below as they reach the surface.
What is Keratinised Compound Epithelial tissue?
The skin has an outer layer of epithelium similar in structure to the stratified epithelium but with the important addition of a layer of dead cells on the outside, this is known as the epidermis. As the cells advance from the basemen membrane, they gradually become filled with a protein called keratin and are said to be keratinised. This layer is vital to prevent micro-organisms invading deeper structures, and it has a waterproofing effect on the skin.
