Provide physical protection Control permeability Provide sensation Produce specialized secretions There are various specialized types of epithelia. They can be sorted by cell shape and the number of cells between the basement membrane and the exposed surface of the epithelium. The three basic shapes of epithelial are squamous, cuboidal, and columnar. If the basement membrane is only covered by one layer of cells it is called a simple epithelium. If the basement membrane is cover by several layers of cells it is called stratified epithelium.
The epidermis is the superficial layer of the skin. It is composed of keratinized stratified squamous epithelium. The dermis is the layer of skin beneath the epidermis. It is composed mostly of dense irregular connective tissue. Skin appendages, which derive from the epidermis, include hairs and hair follicles, nails, and glands.
The outer layer is the epidermis. The dermis is in the middle and fat forms the innermost layer. Blood vessels, nerves, hair follicles, oil glands and sweat glands are located in the dermis. The major function of skin is to provide a barrier between you
Tissues and Tattoos The four types of tissue are epithelia, connective tissue, muscle tissue and neural tissue. They are all different but all serve a general purpose to cover, fill and protect what is underneath. Epithelia cover exposed surfaces, line internal passageways, chambers and produce glandular secretions. Connective tissues are responsible for filling internal spaces, provide structural support and store energy. Muscle tissue contract to produce active movement.
All the substances entering or leaving the body must pass through epithelium and are under its control. The ion-transporting epithelium may become highly specialized for absorption or excretion. * The glandular secretions of the body by glands (exocrine and endocrine) are mainly a function of specialized epithelium. Polarity: Epithelial cells are polarized cells and we can distinguish different areas of the cells (apical, basal, and lateral) with specific structural modifications (unlike other tissues, where structural polarity is not found). Specific structures found on the apical surface
The epidermis is the skins most superficial layer and it is composed of stratified squamous epithelial tissue.2 The epidermis is divided into four or five general layer called the strata. The deepest layer is the stratum basale and it contains a single layer of cuboidal cells. In the epidermis with cells that actively grow and divide to produce new epidermis. The layer that is called the stratum basale is the stratum lucidum is only found on thick skin. The stratum corneum is another layer in the epidermis, and it is the most superficial startum.
Two are canals called the scala tympani and the scala vestibuli. The third is called the organ of Corti. The scala tympani and the scala vestibuli are separated by the cochlear partition. Within the partition is the basilar membrane, and within the basilar membrane are numerous, tiny hair cells. Sound waves travel through the fluid of the cochlea and make the hair cells in the organ of Corti move.
Nervous tissues - Conducts impulses organs from neurons. Simple squamous epithelium cells are made up of a single layer of epithelial cells. They are the point of contact for the epithelial tissue with the base membrane. They can be located in areas that face rapid diffusion and where little activity happens. Stratified epithelial cells consist of two or more layers of epithelial cells.
It is made of connective tissue, containing collagen and elastin. The dermis contains specialised cells, blood vessels and lymphatic vessels as well as nerve endings that inform the brain to heat, cold, pressure and pain. Sweat glands extend from deep in the dermis to the outer layer of the epidermis. Sweat contains mostly water, urea and salts and it helps to control body temperature. Hair follicles are found in the dermis and attached to these are tiny muscles called erector pili.
The nervous system is defined by the presence of a special type of cell, called the neuron. Neurons send signals with rapid precision to other cells with special structures that allow them to accomplish this task. Sensory neurons carry impulses or electrochemical signals to the interneurons of the brain. The interneurons interpret these impulses while the motor neurons carry