Body Membranes 2 types of body membranes Epithelial

Body Membranes � 2 types of body membranes: • Epithelial • Connective

Epithelial membranes �Always composed of 2 things: • An epithelial sheet • And underlying connective tissue • Remember this as we learn about the 3 types of epithelial membranes!!!

The 3 types of epithelial membranes �Cutaneous �Mucous �Serous

Type 1: Cutaneous membrane �Your skin �Epith. tissue: stratified squamous �Conn. tissue: dense fibrous �Functions in covering/protection �Only epithelial tissue that is exposed to air, and so we call it a dry membrane

Type 2: Mucous Membrane �Lining of organs that are exposed to the outside • Nasal cavity and large intestine �Epith. Tissue: stratified squamous or simple columnar �Conn. Tissue: loose areolar �Functions in absorption or secretion

Type 3: Serous membrane �Double lining around organs that are closed to the outside �Epith. Tissue: simple squamous �Conn. Tissue: loose areolar �Filled with serous fluid, which prevents the organ’s walls from creating friction against any other body organs

Serous membrane continued �There is an inside and an outside to this lining: • Parietal layer lines the outside of the membrane • Visceral layer lines the inside covering the organ

Connective Tissue Membranes: �Composed of only connective tissue, contain no epithelial cells � 2 types: § Synovial § Meningeal

Connective Tissue Membranes �Synovial membranes- line the capsules around joints, provides a smooth surface while also secreting lubricating fluid

Connective Tissue Membranes: �Meningeal or meninges- 3 membranes that surround the brain and spinal cord. Protect and keep them bathed in cerebrospinal fluid.