Transcript CELL WALL
Presenting: THE CELL WALL PRESENTED BY: DeVaughn Patterson and Jason Palonis Functions of the Cell Wall • • • • • • Found outside cell membrane it lends the cell stability, it determines its shape, influences its development, acts as a filtering mechanism, protects the cell against pathogens (viruses, bacteria, fungi, etc.) • counterbalances the osmotic pressure. So what has a Cell Wall ? Cell Walls are found in Plants, Fungi, Algae, some Archaea and Bacteria. * Protozoa and Animals do NOT have cell walls. So what has a Cell Wall ? -andWhat are Cell Walls made of? -Plants have Cell Walls Eukaryotic Plants actually have 2 Cell Walls •In plants, the strongest component of the complex cell wall is a carbohydrate called cellulose, which is a polymer of glucose. •Primary Cell Wall- generally a thin, flexible and extensible layer formed while the cell is growing. •Secondary Cell Wall- a thick layer formed inside the primary cell wall after the cell is fully grown. • Strengthens and waterpoofs the wall. • *It is NOT found in all cell types. •Middle Lamella- a layer rich in pectins, glues 2 adjacent cell walls together. -Fungi have Cell Walls •Eukaryotic •Fungi possess cell walls made of the glucosamine polymer chitin. (a derivative of glucose). •True fungi do not have cellulose in their cell walls -Algae have Cell Walls • Eukaryotic • Algae typically possess walls made of glycoproteins and polysaccharides. -some Archaen have Cell Walls •Prokaryotic •Archaean cell walls have various compositions. •May be formed of glycoprotein or polysaccharides. •Unlike Bacteria, all Archaen cell walls lack peptidoglycan. -Bacteria have Cell Walls The Stealth Pathogen •Prokaryotic •In bacteria, peptidoglycan forms the cell wall. •Peptidoglycan- is a carbohydrate matrix (polysaccharides + protein) DEFICIENT A Very Sneaky Bacteria Cell Wall Deficient Forms “The Stealth Pathogen” • The term stealth pathogens refers to bacteria that have cell walls that are deficient in shape, structure, rigidity, and/or layering. • Almost unrecognizable, and omnipresent • They are capable of considerable shape-changing *Shape change enables these bacteria to easily move DNA between cells. This allows groups of bacteria to fuse together, = disease-causing combinations. Examples: -MS -Rheumatoid arthritis, along with other forms of arthritis -Meningitis -Urinary tract infections -Heart valve infection -Eye inflammations -and a host of other maladies TO RECAP: & To Get Us Back On Track- *Cell Walls are found in Plants, Fungi, Algae, some Archaea and Bacteria. *Cell Walls are made of various carbohydrates and proteins. So what does NOT have a Cell Wall Here’s a Hint: Protozoa and…. So what does NOT have a Cell Wall The End . Animals and Protozoa do NOT have Cell Walls. THIS INCLUDES YOU TOO!!!!