Epithelial Tissue in Animal Body

Arrangement of Epithelial Tissue Cells

• Epithelial cells are arranged in continuous sheets, forming either single layers (simple) or multiple layers (stratified).
• Cells are closely packed with minimal extracellular matrix, ensuring a barrier to protect underlying structures.

Epithelial Tissue Identification

• Epithelial tissue does not include connective tissues like bones, cartilage, and adipose tissue.
• Distinction is based on function and structure rather than location within the body.

Importance of Permeability in Epithelial Cells

• Permeability allows selective absorption and secretion, crucial for functions such as nutrient uptake and waste excretion.
• Regulates exchange of substances, protecting underlying tissues while maintaining necessary homeostasis.

Differences from Connective Tissue

• Epithelial tissue has no blood vessels and relies on adjacent connective tissue for nourishment and waste removal.
• Connective tissue is characterized by a significant amount of extracellular matrix, unlike the tightly packed arrangement of epithelial cells.
• Epithelial tissue primarily covers surfaces and forms barriers, whereas connective tissue supports and binds other tissues and organs.

Learn about epithelial tissue, the covering or protective tissues in the animal body that form barriers and separate body systems. Discover how epithelial tissue cells are tightly packed to form continuous sheets in organs and cavities like the skin, mouth lining, blood vessels, lung alveoli, and kidney tubules.