Problems on Concentration 1 mole 6 1023 molecules 1 The molecular weight of glucose is 180 grams per mole 1 mole of glucose weighs 180 grams What is the glucose in moles per liter Molar of a solution consisting of a 180 grams of glucose in one liter 1M b 180 grams of glucose in 2 liters 0 5M c 18 grams of glucose in 100 milliliters recall there are 1000 milliliters in one liter 1 milliliter 1 mL 1M d 90 grams of glucose in 0 5 liters 1M 2 The molecular weight MW of NaCl is 58 4 grams per mol What is the concentration of NaCl in a solution consisting of a 5 84 grams of NaCl in 1 liter 0 1M or 100 millimolar b 58 4 grams of NaCl in 0 5 liters 2M c 29 2 grams of NaCl in 1 liter 0 5M d 29 2 grams of NaCl in 2 liters 0 25M or 250 millimolar Clicker questions Clicker channel 70 Response Ware Session ID psio201 A chemical bond that involves the unequal sharing of electrons such as in water is called a n A B C D 95 ionic bond polar covalent bond hydrogen bond non polar covalent bond 3 2 A B C 1 D Hydrogen bonds are the strongest type of bond in biological systems A True B False 92 8 A B You add 100 micromoles of H to pure water The resulting solution would be acidic basic neutral and its pH would increase decrease stay the same 92 A B C D E Acidic decrease Acidic increase Basic decrease Basic increase Neutral stay the same 3 A B 1 C 3 D 0 E Which of the following molecules is NOT organic 88 A B C D E Triglyceride Glycogen Testosterone DNA Water 4 A 2 B 4 C 2 D E Lecture 3 Cellular Level of Organization I Claudia Stanescu Ph D Office hours Tuesday and Thursday 1 2pm in Gittings 108 or by appointment Note Thursday s office hours for this week moved to Friday 10 11am Objectives pp 27 55 sec 2 5 3 1 3 2 1 List the primary constituents and describe the functional organization of a biological membrane 2 Compare and contrast the structural elements of integral and peripheral membrane proteins that influence their interaction with membranes include the concepts of lipophilicity vs hydrophilicity or alternatively non polar vs polar Explain why the amphipathic structure of phospholipids and integral membrane proteins is important in establishing stable membrane structure 3 Define the terms primary secondary and tertiary structure with respect to the structure of a protein 4 Biological membranes are considered to be fluid structures Discuss the basis of this view The Cellular Level of Organization Cell Theory 1 Cells are the building blocks of animals and plants 2 Cells arise from pre existing cells 3 Cells are the smallest unit having all the functions of living systems 4 Homeostasis of higher levels of biological organization arises from coordinated activity of cells Typical Illustration of a Human Cell Cytoskeleton Microtubule Microfilament Intermediate filament Microvilli Centrosome Pericentriolar material Centrioles PLASMA MEMBRANE Secretory vesicle Lysosome Smooth endoplasmic reticulum ER Peroxisome Flagellum NUCLEUS Chromatin Cilium Proteasome Free ribosomes Nuclear pore Nuclear envelope Nucleolus Glycogen granules CYTOPLASM cytosol plus organelles except the nucleus Rough endoplasmic reticulum ER Membrane bound ribosome Golgi complex Mitochondrion Microtubule Microfilament Generalized Cell Structures Plasma membrane interaction surface between a cell and the world outside of it a k a cell membrane plasmalemma Nucleus contains the genetic material of the cell Cytoplasm everything between the membrane and nucleus intracellular fluid the cytosol subcellular structures with specific functions organelles Let us consider what s actually there http mgl scripps edu people goodsell illustration patterson http mvc bioweb dcccd edu weblinks patterson html Two Categories of Organelle 1 Membranous Endoplasmic Reticulum Nucleus Mitochondria 2 Non Membranous Cytoskeleton Ribosomes Physiological Membrane Composition 1 Lipid The principal membrane lipid is phospholipid 2 Protein 3 Carbohydrate Phospholipid Structure Amphipathic molecule has a polar head group region charged residues and polar covalent bonds polar Phosphate group uncharged residues and C H covalent bonds non polar tail region capable of spontaneous selfassembly non polar Clicker Questions Clicker channel 70 Response Ware Session ID psio201 How would you predict phospholipids to organize when placed in water 90 10 1 2 A 1 A 2 B B Polar head Polar head Phosphate group Nonpolar tails Nonpolar tails Chemical structure of a phospholipid self assembly of phospholipids Polar heads Nonpolar tails In a lipid bilayer polar head groups A interact more with water 98 because water is also polar B interact more with lipid because lipid is also polar C interact more with water because water is non1 polar A B 1 C Plasma Membranes in the Cell What makes one region of plasma membrane different from another What is the basis for the difference in function between different regions of plasma membrane Physiological Membranes Extracellular fluid Glycoprotein Channel protein Pore Lipid bilayer Carbohydrate Protein Glycolipid Peripheral protein Carbohydrate Lipid Cytosol Integral transmembrane proteins Phospholipids Peripheral protein Cholesterol Membrane proteins confer different functionality physiology upon different membranes in cells Proteins are comprised of a linear sequence of amino acids Side chain Amino base group Carboxyl acid group amino acid nonionized Side chain Amino base group Carboxyl acid group amino acid ionized Proteins are comprised of a linear sequence of amino acids Side chain Amino base group Carboxylic acid group amino acid nonionized Proteins are comprised of a linear sequence of amino acids Side chain Amino base group Carboxylic acid group amino acid ionized Proteins are comprised of a linear sequence of amino acids Proteins are comprised of a linear sequence of amino acids Types of Membrane Proteins Integral proteins extend into or completely across cell membranes are amphipathic with hydrophobic portions hiding among the phospholipid tails of the lipid bilayer Peripheral proteins attached to either inner or outer surface of cell membrane and are easily removed from it Physiological Membranes Channel protein Extracellular fluid Glycoprotein Pore Lipid bilayer Carbohydrate Protein Glycolipid Peripheral protein Carbohydrate Lipid Cytosol Phospholipids Integral transmembrane proteins Peripheral protein According to the fluid mosaic model of the cell membrane membrane proteins are free to move laterally throughout the cell membrane How do