tissues

• The primary function of epithelium is protection against mechanical damage or invasion by microorganisms.
• Squamous cells have a flat shape with no nucleus visible under light microscopy.
• Epithelial tissue is the most abundant type of tissue, covering all surfaces that are exposed to the external environment.
• Simple squamous epithelium has one layer of flattened cells.
• Cuboidal cells are cube-shaped, with the nucleus located at one end.
• Epithelial tissue covers the body surface, lines all internal cavities, and forms glands that secrete substances into the bloodstream or other organs.
• Stratified squamous epithelium consists of multiple layers of flattened cells.
• There are four types of epithelia based on shape: simple squamous (thin flat cells), simple cuboidal (cube-shaped cells with nuclei at center), simple columnar (tall cylindrical cells with nucleus near base), stratified squamous (several layers of flattened cells).
• Simple Squamous Epithelium has thin, flat cells arranged in one layer and functions to allow diffusion across it.
• Columnar cells are tall and narrow, with the nucleus located near the base.
• Stratified squamous epithelia consist of multiple layers of flattened cells that protect underlying tissue from abrasion and chemical attack.
• Transitional epithelium lines organs subjected to stretching and distention, such as the urinary bladder.
• Stratified columnar epithelium consists of multiple layers of columnar cells.
• Transitional epithelium can change its thickness depending on the amount of stretching it experiences.
• Pseudostratified columnar epithelium appears stratified but actually only contains one cell layer.
• Mucous membranes line hollow structures such as the mouth, stomach, intestines, and respiratory tract.
• The epidermis is composed of stratified squamous epithelium and contains melanocytes responsible for skin coloration.
• Connective tissue provides support, protection, and insulation to various parts of the body.
• Columnar cells are tall and cylindrical, with the nucleus located near the base.
• Connective tissue provides support, protection, and insulation to various parts of the body.
• Connective tissue provides support, protection, insulation, and storage functions.
• The basement membrane is a thin sheet of connective tissue that anchors an epithelium to underlying connective tissue.
• Blood is a fluid connective tissue composed mainly of plasma and formed elements such as red blood cells, white blood cells, and platelets.
• Simple Cuboidal Epithelium is made up of cube-shaped cells with a single layer and performs secretion and absorption functions.
• Simple Columnar Epithelium contains tall, cylindrical cells with a single layer and functions include secretion, absorption, and sensory reception.
• Connective Tissue provides support, protection, insulation, and storage functions.
• Transitional epithelium is found only in the urinary system and can stretch as needed without breaking apart.