Tejido Epitelial 🔬🤚🛡️ Características, funciones y clasificación 🤓

Summary

Epithelial tissue consists of tightly packed cells with little or no space between them. It has no blood vessels and forms protective coverings and linings throughout the body.

Main functions

• Protection: Covers the body’s surface and lines organs, helping shield them from physical damage, microbes, chemicals, and other hazards.
• Absorption: Takes up nutrients in the intestine and passes them into the blood.
• Exchange and filtration: Allows substances to pass between the body and its surroundings. For example, lung epithelium enables oxygen to enter the blood.
• Secretion: Forms parts of glands that produce substances such as saliva and sweat.
• Sensing stimuli: Helps detect sensations such as heat, cold, and pain in areas including the skin and tongue.

Classification

Epithelial tissue can be classified by the number of cell layers:

• Simple epithelium: One layer of cells.
• Stratified epithelium: Several layers of cells stacked on one another.
• Pseudostratified epithelium: Appears to have multiple layers because its nuclei lie at different heights, but is actually one layer; all cells touch the base.

It can also be classified by cell shape:

• Squamous (flat): Thin, wide cells.
• Cuboidal: Roughly cube-shaped cells, found in some gland ducts.
• Columnar (cylindrical): Tall, elongated cells, such as those in the intestine.

Overall, epithelial tissue is widespread and performs many roles beyond protection.

Speakers and sources

• Speaker: An educational narrator or voiceover; no individual speaker is identified in the subtitles.
• Source: “Tejido Epitelial 🔬🤚🛡️ Características, funciones y clasificación 🤓” — Profe Marilin.