PPT-Cell Membrane

Learning Objectives outline the roles of membranes within cells and at the surface of cells state that plasma cell surface membranes are partially permeable barriers describe with the aid of diagrams the fluid mosaic model of membrane structure. بسم الله الرحمن الرحيم. Objectives. Define Membrane . Potential. ?. Describe the electrical potential across the cell membrane.. Explain the Resting . Membrane and its cause . (Concentration . -. Gateway to the Cell. 2. Photograph of a Cell Membrane. 3. Cell Membrane. The cell membrane is . flexible. and allows a . unicellular. organism to . move. 4. Homeostasis. Balanced. internal condition of cells. . By Dr. . Vani. Gupta. 2. “Polarity” . of the . membrane. Na. +. K. +. Mg. 2+. Ca. 2+. H. +. HCO. 3. -. Cl. -. SO. 4. 2-. PO. 3. -. protein. inside. (in mM). 14. 140. 0.5. 10. -4. (pH 7.2). 10. and Transport. Cell Membrane. Cell membrane- also called the . Plasma Membrane. Separates the cell from its surrounding . environment.  . Helps maintain homeostasis which is keeping the internal conditions constant. Summary. How do materials get across a cell's membrane. ?. It depends on the type of substance. Summary. Non-polar materials or hydrophobic materials . do. cross easily, especially if small. Ex – CO. Cell Membrane and Cell Wall:. . ALL. . cells have a . cell membrane. made of . proteins. and . lipids. . Cell Membrane. lipid bilayer. protein channel. protein . pump. Layer 1. Layer 2. SOME. cells have cell membranes . “Head” regions of phospholipids are hydrophilic, so love water. “Tail” regions are hydrophobic, so fear water and “hide” from it. In other words, cells membranes form in water because they HAVE to!. Learning . Goal . Describe . the composition and function of the lipid bilayer in cell membranes.. Cell Membranes. Cell membranes. . are semipermeable so that nutrients can enter the cell and waste products can leave.. Figure 4.13c. Figure 4.13b–c. Gram-Positive Gram-Negative . Cell Walls Cell Walls. Thick peptidoglycan. Teichoic acids. In acid-fast cells, contains mycolic acid. Thin peptidoglycan. No teichoic acids. Unit Objectives. 1: Explain the structures of plant cells and important cell processes.. a. Describe the structures of a typical plant cell and their functions.. b. Compare and contrast mitosis and meiosis.. Structure. Main component is phospholipids that are arranged in a double layer (. bilayer. ). Has scattered proteins within the phospholipids. Regulate what enters/leaves cell. Function . Nucleus. Structure. How was it discovered?. http://. ed.ted.com. /lessons/insights-into-cell-membranes-via-dish-detergent-ethan-perlstein#watch. The Plasma Membrane. What is the plasma membrane?. Flexible, sturdy barrier of the cell.. What is the plasma membrane?. A flexible boundary between the cell and its environment which maintains . HOMEOSTASIS. within the cell. **Remember that . HOMEOSTASIS. is a state of balance/equilibrium within the cell.. Much larger than prokaryotic cells having two enveloped systems. True cells occurring in plants and animals . Though they have different shape size and physiology but all cells are typically composed of plasma membrane cytoplasm and its organelles i.e. mitochondria, endoplasmic reticulum .