Lecture 6 and 7
Lecture 6 and 7 Biol 202
Popular in Human Anatomy and Physiology I
Popular in Biology
verified elite notetaker
This 15 page Class Notes was uploaded by Natasha on Friday September 18, 2015. The Class Notes belongs to Biol 202 at St. Cloud State University taught by Schoenfuss, Heiko in Spring 2015. Since its upload, it has received 53 views. For similar materials see Human Anatomy and Physiology I in Biology at St. Cloud State University.
Reviews for Lecture 6 and 7
Report this Material
What is Karma?
Karma is the currency of StudySoup.
Date Created: 09/18/15
Notes Bio 202 Lecture 6 by William Heikkila Chapter 2 Chemistry Comes Alive Part A Matter anything that occupies space and has mass 0 Matter has three states 0 Solid definite shape and volume 0 Liquid changeable shape but a definite volume 0 Gas changeable shape and a changeable volume Mass actual amount of matter a substance Weight varies with gravity force of gravity pulling mass down Energy the capacity to do work or to put matter into motion 0 Kinetic Energy energy in action motion like moving a muscle 0 Potential Energy store energy inactive energy that has potential compressed spring it has potential energy 0 Energy can be transferred from potential to kinetic energy Releasing the spring would be kinetic energy because it would be in motion Forms of Energy 0 Chemical Energy stored in bonds of chemical substances food we eat Electrical Energy results from the movement of charged particles nerve cells Mechanical Energy energy directly involved in moving matter physical energy Radiant Energy or Electromagnetic Energy energy that travels in waves Xrays light rays infrared waves radio waves etc Energy form Conversions Energy is easily converted from one form to another Energy conversions are quite inefficient Some of the initial energy is always lost to the environment as heat This is important because it helps us stay at 986 degrees Fahrenheit Composition of Matter Elements 0 All matter is composed of elements 0 Element unique substance that cannot be broken down into simpler substances by ordinary chemical methods 0 Each element has unique properties 0 Physical properties I Detect with our senses color and texture or measure boiling point and freezing point 0 Chemical properties I The way atoms interact With other atoms covalent bonds ionic bonds hydrogen bonds Composition of Matter Atoms Atoms unique building blocks for each element Give each element its physical and chemical properties Smallest particles of an element With properties of that element Atomic Symbol O 0 One or two letter chemical shorthand for each element Periodic Table of Elements Elements in the Human Body Four elements make up 961 of body mass 0 O O 0 Carbon C Hydrogen H Oxygen O Nitrogen N Nine elements make up 39 of body mass 0 0000000 0 Calcium Ca Phosphorus P Potassium K Sulfur S Sodium Na Chlorine Cl Magnesium mg Iodine 1 Iron Fe Eleven elements in very minute amounts make up lt001 of body mass 0 0000000000 Chromium Cr Cobalt Co Copper Cu Fluorine F Manganese Mn Molybdenum Mo Selenium Se Silicon Si Tin Sn Vanadium V Zinc Zn Atomic Structure Atoms are composed of subatomic particles 0 Protons I Found in the Nucleus I Carry positive charge I Mass 1 atomic mass unit amu O Neutrons I Found in the Nucleus I Carry no charge I Mass 1 atomic mass unit amu O Electrons I Orit nucleus in electron cloud I 12000 the mass of a proton 0 amu 0 The numbers of protons and electrons are always equal Models of the Atom 0 Planetary model simple and outdated O Incorrectly depicts fixed circular electron paths 0 Useful for illustration in a text I Orbital model current model 0 Probable regions of greatest electron density an electron cloud 0 Useful for predicting chemical behavior of the atoms Identifying Elements 0 Atomic Number number of protons in nucleus 0 Written as subscript to left of atomic symbol 3Li O 3 protons is always Li in some shape or form 0 Mass Number total number of protons and neutrons in nucleus total mass of atom 0 Written as a superscript to left of atomic symbol 7Li I Isotopes 0 Structural variations of atoms 0 Differ in the number of neutrons they contain 0 Atomic numbers are the same but mass numbers are different 0 Atomic Weight 0 Average of mass numbers of all isotopes of an atom 0 Radioisotopes 0 Heavy isotopes decompose to more stable forms Spontaneous decay is called radioactivity Can transform into a different element It can be detected With scanners It is valuable for tools in biological research and medicine diagnosis All damage living tissue destroy localized cancers overactive thyroid OOOOO Combining Matter Molecules and Compounds 0 Most atoms chemically combine With other atoms to form molecules and compounds 0 Molecule two or more atoms bonded together H2 0 Compound two of more DIFFERENT kinds of atoms bonded together C6H1206 Mixturestwo or more components physically intermixed 0 Solutions 0 Homogeneous mixtures Most are true solutions in the body Solvent Substance present in the greatest amount usually a liquid Solute present in smaller amounts Ex Salt water Salt is the solute and water is the solvent Can be expressed as parts solute per 100 parts of solvent Milligrams per deciliter mgdl like blood glucose levels Molarity or moles per liter I 1 mole of any substance equals Avogadro s number 0000000 0 Colloids O Heterogeneous mixture 0 Large solute particles do not settle out 0 Some undergo solgel transformations cytosol during cell division 0 Ex Gelatin or J ellO 0 Suspensions O Heterogeneous mixtures blood 0 Large visible solutes that settle out on the bottom Mixtures vs Compounds 0 Mixtures O No chemical bonding occurs between components 0 Can be separated by physical means like boiling straining or filtering 0 Homogeneous or heterogeneous 0 Compounds 0 Chemical bonding between components 0 Can be separated only by breaking bonds 0 All are homogeneous Chemical Bonds 0 Chemical bondsenergy relationships between electrons of reacting atoms 0 Electrons occupy up to seven electron shells around the nucleus 0 Electrons in the valence shell have the most potential energy and are chemically reactive to elements 0 Octet rule rule of eights 0 Except for the first shell full with two electrons atoms interact to have eight electrons in their valence shell 0 Nobel gasses are chemically inert gasses because their octet is full They are stable and unreactive If the valence shell is not full they tend to gain lose or share electrons form bonds with other atoms to achieve stability Types of Chemical Bonds 0 Ionic Bonds 0 Ions atom gains or loses electrons and becomes charged number of protons does not match the number of electrons 0 Transfer of valence shell electrons from one atoms to another forms ions I Anion negative charge atoms that gained one or more electrons 39 Cation positive charge atoms that lost one of more electrons O Attraction of opposite charges results in an ionic bond 0 All salts are ionic bonds NaCl left side of the table bonding to the right side of the table 0 Covalent Bonds 0 Formed by sharing two or more valence shell electrons Allows each atom to fill its valence shell at least part of the time Form single double or triple bonds Nonpolar covalent bondselectrons are shared equally Polar covalent bonds electrons are not shared equally electronegative and electropositive sides 0 Hydrogen Bonds 0 Attractive force between electropositive hydrogen of one molecule and an electronegative atoms of another molecule 39 Not true bonding 39 Common between dipoles like water I Act as intramolecular bonds holding a large molecule in a three dimensional shape 0 O O 0 Chemical reactions occur when chemical bonds are formed rearranged or broken 0 Represented as chemical equations using molecular formula 0 Equation contains reactants and products Reactant Product H H I H2 hydrogen gas 4HC I CH4 Methane Patterns of Chemical Reactions 0 Synthesis combination reactions 0 A B I AB 0 Atoms of molecules combine to form larger more complex molecules 0 ALWAYS involve bond formation 0 Anabolic 0 Decomposition reactions O ABDAB 0 Molecule is broken down into smaller molecules or its constituent atoms reverse of synthesis reactions 0 Involve breaking bonds 0 Catabolic 0 Exchange reactions 0 AB C I AC B 0 Also called displacement reactions 0 Involve both synthesis and breaking of bonds 0 Bonds are both made and broken OxidationReduction Reactions 0 Are decomposition reactions food fuels are broken down for energy 0 Are also exchange reactions because electrons are exchanged between reactants O Electrons donors lose electrons and are oxidized 0 Electron acceptors receive electrons and are reduced C6H1206 602 I 0 Glucose is oxidized and the oxygen molecule is reduced Energy Flow in Chemical Reactions 0 Exergonic reactions no net release of energy 0 Products have less potential energy than reactants O Catabolic and oxidative reactions 0 Endergonic reactions net absorption of energy 0 Products have more potential energy than reactants O Anabolic reactions Reversibility of Chemical Reactions 0 All chemical reactions are theoretically reversible o A B I AB 0 AB I A B 0 Chemical equilibrium occurs if neither a forward nor reverse reaction is dominant 0 Many biological reactions are essentially irreversible 0 Due to energy requirements and removal or products Rate of Chemical Reactions 0 Affected by 0 Increase Temperature I Increase Rate 0 Increase Concentration of reactant I Increase Rate 0 Decrease particle size I Increase Rate 0 Catalyst increase rate Without being chemically changed or part of produce I Enzymes are a biological catalyst Bio 202 Lecture 7 Chapter 2 Chemistry Comes Alive Part B Biochemistry the study of chemical compositions and reactions of living matter Classes of compounds 0 Organic compounds 0 Contain carbon 0 Carbohydrates fats proteins and nucleic acid 0 Inorganic compounds 0 Water salts and many acids and bases 0 Do NOT contain carbon 0 6080 water in living cells Water Properties 0 High heat capacity 0 Absorbs and releases heat With little temperature change 0 High heat of evaporation 0 Needs large amounts of heat 0 Useful in cooling mechanisms 0 Polar solvent properties 0 Body s major transport system 0 Forms hydration layers around large charged molecules 0 Dissolves and dissociates ionic substances 0 Reactivity O Necessary part of hydrolysis and dehydration synthesis 0 Cushioning 0 It protects some organs from physical trauma Salts 0 Are ionic compounds that dissociate into ions in water 0 Ions or electrolytes conduct electrical currents in water solution 0 Ions play a special role in body functions sodium potassium calcium amp iron 0 Ionic valance vital for homeostasis 0 Contain cations other than H and anions other than OH39 0 Common salts in the body are NaCl C3CO3 KCl calcium phosphate Acids and Bases 0 Both are electrolytes ionize and dissociate in water 0 Acids are proton donors 0 Important acids are HCl HC2H302 and H2C03 0 Bases are proton accepters 0 Important bases are bicarbonate ion and ammonia pH Acidbase concentration 0 Relative free H of a solution measured on pH scale As free H increase acidity increases 0 OH39 decreases as H increases 0 pH decreases 0 As free H decreases alkalinity increases 0 OH39 increases as H decreases 0 pH increases 0 pH negative logarithm of H in moles per liter 0 pH scale ranges from 014 0 pH scale is logarithmic Acidic solutions 0 Increase H decreases the pH 0 Acidic pH goes from 0 to 699 Neutral solutions 0 pHof7 0 pure water is neutral Basic solutions 0 Decrease in H and increase in pH 0 Basic pH goes from 70114 Neutralization mixing acids and bases together water and a salt Acidbase homeostasis 0 pH change interferes With cell function and can damage liVing tissue 0 small changes in pH can be fatal 0 pH is regulation by kidneys lungs and chemical buffers Buffers 0 Acidity re ects only free H in solution 0 Buffers resist abrupt and large swings in pH 0 Convert strong acids or bases into weak ones 0 Carbonic acidbicarbonate system Organic Compounds 0 Molecules that contain carbon not CO and C02 0 Unique to liVing systems 0 Carbohydrates lipids proteins and nucleic acids 0 Many are polymers 0 Synthesized by dehydration synthesis 0 Broken down by hydrolysis reactions Carbohydrates 0 Sugars and Starches 0 Polymers 0 Contain C H and O 0 Three classes 0 Monosaccharides one sugar 0 Disaccharides two sugars O Polysaccharides many sugars 0 Function as major sources of cellular uid glucose and structural molecules ribose in RNA sugar Monosaccharides 0 Simple sugars contain 3 to 7 carbon atoms 0 CHZOr1 is the general formula 11 is the number of Carbon atoms 0 Monomers of carbohydrates 0 Pentose and hexose are important monosaccharides Disaccharides 0 Double sugars 0 Too large to pass through a cell membrane 0 Sucrose maltose and lactose are important disaccharides Polysaccharides 0 Polymers of monosaccharides 0 Starch and glycogen are important polysaccharides 0 Not very soluble Lipids 0 Contain C H O and sometimes P 0 Insoluble in water 0 Triglycerides 0 Or Neutral fats Fats when solid and oils when liquid Composed of three fatty acids bonded to a glycerol backbone Energy storage insulation and protection are the main functions Saturated fatty acids contain a single covalent bond 0 Unsaturated fatty acids contain a double covalent bond 0 Phospholipids 0 Modified triglycerides with two fatty acids and a P group 0 Important to cell membrane structure 0 Polar head and nonpolar tail 0 Steroids 0 Four ring system 0 Cholesterol Vitamin D steroid hormones and bile salts 0 Cholesterol is an important steroid 0 Eicosanoids 0 Many types 0 Prostaglandins are the most important they clot blood control blood pressure in ammation and labor contractions 0000 Other lipids are fat soluble Vitamins A D E and K Lipoproteins transport fats in the blood Proteins 0 Contain C H O N and sometimes S and P 0 Polymers 0 20 types of amino acids monomers of proteins 0 Join by peptide bonds 0 Either acid or base 0 Different R group Fibrous proteins 0 Strandlike water insoluble and stable 0 Tertiary or quaternary structure 0 Support and tensile strength 0 Keratin elastin collagen and certain contractile fibers Globular proteins 0 Compact spherical water soluble and sensitive to temperature 0 Tertiary or quaternary structure 0 Have specific functions or active signs on regions 0 Antibodies hormones molecular chaperones and enzyme Protein Denaturation 0 Globular proteins unfold and lose their function caused by decrease pH or increase temperature 0 Can be reversible if normal conditions are restored quickly 0 Irreversible is like cooking an egg Molecular chaperone Globular protein 0 Ensure quick accurate folding and association of other proteins 0 Prevent incorrect folding 0 Assist in translocation of proteins and ions across membranes 0 Promotes breakdown of damaged or denatured proteins 0 Helps trigger the immune system response 0 Stress proteins 0 Produced in response to the stressful stimuli 0 Important to cell function during stress 0 Can delay aging by patching up damaged proteins and refolding them Enzymes 0 Globular proteins that as biological catalysts regulate increases in speed of chemical reactions 0 Lower the activation energy and increase the speed of a reaction Characteristics of Enzymes Holoenzymes O Apoenzyme O Cofactor or coenzyme Specific act on a specific substrate Usually end in ase Often named for the reaction they catalyze hydrolases oxidases Nucleic acids DNA DNA and RNA largest molecules in the body Contain C O H N and P Polymers 0 Monomer nucleotides 0 Nitrogen base pentose sugar and phosphate group Purine Adenine A and Guanine G Pyrimidines Cytosine C and Thymine T Base pair rule each base paid is always With the compliment base AT GC Double helix Pentose sugar is deoxyribose Provides instructions for protein synthesis Ensures genetic continuity Adenine A Cytosine C Guanine G and Uracil U Pentose sugar is ribose Single strand mRNA tRNA and rRNA ATP 0 Chemical energy in glucose captured in this molecule 0 Powers chemical reactions in the cell 0 Used immediately by all cells in the body 0 Structure of ATPcontains adenine With RA nucleotides With two phosphate groups Function of ATP 0 Phosphorylation 0 Terminal phosphates are enzymatically transferred to and energize other moleculesperform cellular work using the phosphate bond energy