What type of tissues form the outer and inner surfaces of organs and structures throughout the body?

Epithelial tissues are specialized for covering and protecting surfaces throughout the body, both externally and internally. These tissues form the outer layer of skin and line various cavities and organs, including the lining of the gastrointestinal tract, respiratory tract, and blood vessels. Their structure is characterized by tightly packed cells with minimal extracellular matrix, allowing them to create effective barriers and facilitate functions such as absorption, secretion, and sensation.

Epithelial tissues can be classified based on their cell shape (squamous, cuboidal, columnar) and the number of layers they form (simple or stratified), which further defines their specific functions in different parts of the body. The adaptability and versatility of epithelial tissues are vital for maintaining the integrity and functionality of organs, highlighting their crucial role in overall bodily health.

Connective tissues primarily support and bind other tissues, muscle tissues are involved in movement, and nervous tissues are responsible for transmitting signals throughout the body, but none of these focus on forming surfaces like epithelial tissues do.