KIN 292 1st Edition Lecture 3Outline of Last Lecture I. Organization of the Human BodyII. Homeostasis: A Central Organizing Principle of Physiology III. The Diabetes EpidemicOutline of Current Lecture I. Biomolecules:a. Molecules synthesized by living thingsb. Contain carbon, 4 unpaired electronsII. Four basic types:a. Carbohydratesb. Lipidsc. Amino acids and proteinsd. NucleotidesCurrent LectureBiomolecules - Unpaired electrons are shared between atoms to formcovalent bonds. - Chem Review p. 22Is this molecule polar or nonpolar?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.- Its polar because one of the atoms (oxygen, which is negative but strong) binds the other (hydrogen, which is positive but weak).- Polar vs. Nonpolar- o Polarity affects diffusion of cells and your hormoneso Fats are always nonpolar because of their covalent bond (which means they share electrons equally)o Water is polar because of the oxygen element; very electronegativeo Glucose and proteins are also polaro Example: Steroids are a fat, so they are non-polar and made on demandCarbohydrates- Composed of carbon, hydrogen, and oxygen- General formula: Cn(H2O)n = (CH2O)n- Primary role in body – energy source- Three types:o Monosaccharideso Disaccharides – covalent bonding of 2 monosaccharides. Sucrose; lactoseo Polysaccharides – covalent bonding of several monosaccharides. Glycogen; cellulose- Monosaccharides o Note the hydroxyl groups: These make carbohydrates polaro Three different monosaccharides with the same chemical formula: C6H12O6o Form ring structures - Condensation vs. Hydrolysis o Formation (synthesis) of sucrose from glucose and fructose is a condensation reaction – meaning water is produced. Common for synthesis of almost all biomolecules.Two elements make up water (gas to liquid). Why is it necessary to remove H and OH from the respective monosaccarides?So a covalent bond can be formed between glucose and fructose o Bond is between carbon. Pulls hydrogen away and then they stickand hold onto each other (referring to the diagram)o Breakdown of sucrose in your stomach to glucose and fructose is a hydrolysis reaction – meaning water is used to break the bond.Hydrolysis is common for almost all breakdown reactions ofbiomolecules. Two items are broken down. o Returning the H (referring to picture)Glycogen- a polysaccharide- Glucose is stored as glycogen in muscles and liver by the process of glycogenesis. It’s a stored energy source. Store max of about 500 g in body – can slightly increase with glycogen loading procedures. When glucose cannot be stored as glycogen or used immediately for energy, it is converted to fat.- Like gas or fuel Cellulose- a polysaccharide - we cannot digest and absorb it because we cannot hydrolyze the β bonds between glucose units- most abundant natural resource (75 billion tonnes annually)- bio-polysaccharide with hierarchical chiral structure- stable and physiologically inert Lipids- Also composed of carbon, hydrogen, and oxygeno Nonpolar covalent bondso Hydrophobic- Five classes – with examples of roles in body:o Triglycerides - energyo Ketones – produced when glucose use is limited Too much ketone is not good for your bodyo Phospholipids – structure, transporto Eicosanoids – intracellular signalingo Steroids – hormones, membrane structure (Cholesterol)- Triglycerideso Stored in fat pads mostly – unlimited storage capacityo Triglyceride = glycerol + three fatty acidso Glycerol = three-carbon alcoholo Fatty acid = long chain of many C and H atoms containing even number of carbons with only 2 oxygen atoms (located at one end). Can be saturated or unsaturated - Ketoneso In diabetes (or low-carbohydrate diets):o When adequate amounts of glucose are unavailable as an energy source, extra hydrolysis of triglycerides in adipose tissue occurs and much Free fatty acids are released in bloodo Some free fatty acids converted to ketones by the livero Acetoacetic acid, acetone, -hydroxybutyric acid o Buildup = ketosis (ketoacidosis)o Acetone breath- Phospholipids o Phospholipids are amphipathic moleculeso Polar head and Nonpolar tailo Reaction of phospholipids with water createsunique structureso Surfactant: Phospholipid in the lungs thatprevents lung collapseMicelles allow lipoproteins/cholesterol to travel in aqueousplasmaEicosanoids - Modified fatty acids that function in intracellular communication. We’ll see them doing this in about a month- Derived from arachidonic acid (20-carbon polyunsaturated fatty acid) found in cell membranes- Examples: Prostaglandins, thromboxanesSteroids- All steroids are derived from cholesterol and have the same base structure of 3 six carbon rings and 1 five carbon ring. They vary in what is attached to the rings- Examples: Estrogen, testosterone, aldosteroneProteins- Polymers (chemical chain) of amino acids- Amino acids- Building blocks of proteins- 20 different kinds of amino acidso Peptide bonds  Formation of a peptide bond by a condensation reaction Proteins have >50 amino acids.  Shorter chains are called peptidesHydrophilic (polar) head(phosphate-containing group)Glycerol backboneHydrophobic (nonpolar) tails(two fatty acid chains)Levels of Protein Structure - Primary – order of the sequence of aminoacids connected by peptide bonds- Secondary – folding pattern caused by weakhydrogen bonds between amino and carboxylgroups in the polypeptide chain. P 31 chemreview- Tertiary – folding pattern caused by variousbonds and forces among R groups in the chain- Quaternary – when multiple polypeptidechains make up a protein. Ex: hemoglobin – 4chains- Proteins can be classified as Fibrous or Globular- Examples of roles of proteins: intracellular chemical messengers, receptors, carrier proteins, enzymes, transport proteins. Nucleotides and Nucleic Acid- Classificationso Energy transfero Chemical messengerso Genetic material- Nucleotide structureo Phosphate group(s) - almost alwayso Five-carbon carbohydrate o Either Riboseo Deoxyribose- Base-containing carbon–nitrogen ringo Pyrimidines (cytosine, thymine, uracil)o Purines (adenine, guanine)- Energy-Transferring Nucleotideso Adenosine di(tri)phosphate (ADP/ATP)  Adenine + ribose + 2 or 3 phosphates Adenine + ribose = adenosineo Nicotinamide adenine dinucleotide (NAD) AKA: Vitamin B3 or Niacino Flavin