ESS 205 Anatomy and Physiology Lecture 6 Outline of Last Lecture I. Permeability of Plasma Membranea. Two classificationsII.Passive TransportIII.Active TransportIV. Carrier MediatedV. Non Carrier MediatedOutline of Current LectureI. Stratified Epithelia II. Connective TissueCurrent Lecture1. The stratified Epithelia are named for the shape of surface cells, called apical cells. It is stratified meaning it has more than one layer. There are also two different variations ofstratified epithelia. The first is keratinized. Keratinized means a surface layer of dead cells. The other is non-keratinized which lacks a layer of dead cells. The major function of stratified epithelia tissues is to protect.a. Keratinized Stratified Squamous retards water loss and prevents penetration of organisms. It is on the epidermal layer of skin and is what prevents millions of bacterial infections or diseases. The moment there is a cut in your skin however, puts you at risk for getting an infection or disease. **Possible test question: How many bacteria are on one square inch of skin? 32 million**b. Non-Keratinized Stratified Squamous is abrasion resistant, moist, and slippery. Examples would be tongues, the esophagus, the vagina and oral mucosa. c. Stratified Cuboidal is only two to three layers. It secretes sweat via sweat glands and milk via mammary glands. *Note it has very few layers because of its function*d. Stratified Columnar is only apical cells and there is limited distribution of this tissue. It is in the male urethra and glandular ducts. These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.e. Transitional is the last stratified epithelial tissue. It forms a lining in urinary organs. This tissue allows a lot of stretching (think bladder) and therefore looks like two different kinds of tissues. When it is not being stretched it looks like stratified cuboidal. Depending on the degree of stretch is starts to look more and more like stratified squamous. 2. Connective tissues are widely spaced cells that are separated by fibers and a ground substance or “matrix.” It is the most abundant and variable of tissue types and primarily connects organs together, gives support/protection, storage of energy/heat production, and movement/transport of materials. 3. There are 6 different cells of connective tissue. The first is a fibroblast which produces fiber and ground substance. Any time a word ends in “blast,” think to build. Next are macrophages. These cells phagocytize, meaning “eat” foreign matter and activate immune system. Neutrophils search for bacteria. Plasma cells synthesize antibodies (think of plasma donation centers). Mast cells secrete heparin that inhibits clotting andhistamine that dilates blood vessels. Lastly, are Adipocytes. Also known as fat cells that store triglycerides. 4. There are three different types of fibers in connective tissue. The first is Collagen Fibers. They are tough, resist stretch yet are flexible. They make up tendons, ligaments, and deep layers of skin. Collagen fibers are the strongest and most abundant and appear to be a pearly white. Next are Reticular Fibers. These are thin collagen fibers that are coated in glycoprotein. They are the framework for the spleen and lymph nodes. Elastic Fibers are the last fibers of the connective tissue. They are thin branching fibers made of elastin. They stretch and recoil like a rubber band. They are in the skin, lungs, and arteries. *Elastic does not mean how FAR it can stretch. It means how FAST it can reset or take its original form again***PLEASE NOTE: Fiber and Cells are not synonymous. **5. Last is the Ground Substance of connective tissue. It is gelatinous or a rubbery material. It is found between cells, and protects by absorbing compressive forces. It gets its consistency from three large classes of molecules:a. Glycosaminoglycanb. Proteoglycanc. Adhesive Glycoproteins that act like tissue