What are squamous epithelial cells?

Friends who are familiar with medical knowledge will definitely know that human skin is just a general term. It can be called a system, and there are many types of skin. For example, epithelial tissue is a relatively large type of skin. Epithelial tissue is subdivided into many different categories. So, what kind of skin is medically referred to as dactyloid epithelial cells?

Squamous epithelial cells are a type of epithelial cell tissue. First, let us understand epithelial tissue. Epithelial tissue, also called epithelium, is an important structure that lines or covers other tissues. It is composed of dense epithelial cells and a small amount of intercellular matrix. The structural characteristics are that the cells are tightly bound and there is little intercellular matrix. It usually has the functions of protection, absorption, secretion and excretion. Epithelial tissue can be divided into three categories: covering epithelium, glandular epithelium and sensory epithelium. The covering epithelium is divided into squamous epithelium, columnar epithelium, cuboidal epithelium, and transitional epithelium according to the shape of its cells in the section perpendicular to the epithelial surface.

Distributed on the surface of the body and the surfaces of various luminal walls in the body.

The covering epithelium is divided into simple epithelium and stratified epithelium according to the number of cell layers:

Simple epithelium includes simple flat (squamous) epithelium, simple cuboidal epithelium, simple columnar epithelium (some with cilia), and pseudostratified columnar epithelium (some with cilia); stratified epithelium includes stratified flat (squamous) epithelium and transitional epithelium. The epithelium has protective, absorptive, secretory and excretory functions, which can prevent damage from foreign objects and invasion of pathogens.

Simple epithelium is composed of a single layer of cells and is often found in areas where substances can pass easily. The pigmented layer of the retina of the eye is a single layer of cuboidal epithelium. The pseudostratified epithelium is distributed on the inner surfaces of the nasal cavity, larynx, trachea, bronchi, etc. It looks like a multilayer, but is actually composed of single layers of cells of different heights. The lower ones are goblet cells, which secrete mucus; the upper ones are ciliated cells, which sweep away inhaled dust particles that are caught by the mucus layer.

The epidermis of the skin, the surfaces of the mouth, esophagus, anus and vagina, and the cornea of ​​the eye are stratified epithelia. Stratified epithelium is composed of multiple layers of cells and is more conducive to protection.