histology

What are general characteristics and functions of epithelial tissue?

Epithelial tissue is characterized by closely packed cells with minimal extracellular matrix. It covers surfaces, lines cavities, and forms glands. Functions include protection, absorption, secretion, and filtration.

Describe simple squamous epithelium: structure and location.

Simple squamous epithelium consists of a single layer of flattened cells, ideal for diffusion and filtration. It is found in the air sacs of the lungs (alveoli) and lining blood vessels (endothelium).

Describe simple cuboidal epithelium: structure and location.

Simple cuboidal epithelium is a single layer of cube-shaped cells, specialized for secretion and absorption. It is located in kidney tubules and glands.

Describe simple columnar epithelium: structure and location.

Simple columnar epithelium is a single layer of tall, column-shaped cells, often with microvilli for absorption or cilia for movement. It lines the gastrointestinal tract.