bio 111 unit 1 - Unit 1 Unit Bio 111 The Scientific Method...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Unit 1 Unit Bio 111 The Scientific Method The What is it? Step by step process Step to answer a question or solve a problem. or Is it limited to Is science? science? No, you use the No, scientific method every day too! every 2 Steps in Scientific Method Steps Observation You notice something of interest to you Question Your observation leads to a question Collect preliminary information to educate yourself about Collect your observation and question your Hypothesis An educated guess as to what the answer is to your question Prediction If the hypothesis is correct then… 3 Steps in Scientific Method Steps Experiment The way you test your hypothesis Results will either support or refute your hypothesis Experimental Group Group given test substance (variable) Control Group Group not given the test substance (variable) Used for comparison to the experimental group 4 Steps in Scientific Method Steps Results Just the facts please! Data collected from your experiment Written Tables Graphs Conclusion Explanation of your results What do the results mean? Do they support or refute your What hypothesis? hypothesis? 5 HEAT UP THE COMMON COLD Researchers in France and Israel have shown that the common cold can be cured in one day by the sufferer breathing warm water vapor. Research in the 1940's and 1950's revealed two key facts linking colds to temperature: colds are caused by viruses, and viruses reproduce only within a narrow temperature range. At body temperature cold viruses reproduce poorly and at high temperatures not at all. They live and reproduce in the nose because the air moving through the nasal passages makes it cooler than the rest of the body. Researchers suspected that if they could increase the nasal air temperature they might be able to cure the cold faster. In an attempt to cure the common cold, French and Israeli researchers built a machine called the Rhinotherm that produces 109 degree Fahrenheit water vapor, which cold suffers inhale through two small tubes. The cold suffers breathed the vapor for three half­hour sessions a few hours apart. Colds were gone within one day in 72 percent of the cold sufferers using the Rhinotherm compared to 5 percent of the cold sufferers using no treatment. 6 Theory Theory What is a theory? More specific than a hypothesis General explanation of a natural phenomena First started out as a hypothesis Much support for the hypothesis over a long period of time Cell theory All living things are composed of cells 7 The study of life The Biology What is life? How do you know that How something is alive? something Characteristics or life Properties shared by living Properties things and not shared by nonliving objects nonliving 8 Living Things are Both Complex and Organized and Salt is organized but not Salt complex complex Ocean water is complex Ocean but not organized but Daphnia are both complex and organized complex 9 Levels of Organization of Matter Levels 10 Basic Unit of Life: The Cell Basic Prokaryotic Cell Lack nucleus Lack many organelles Eukaryotic Cell Membrane bound Membrane nucleus nucleus Complex organelle Complex system system 11 Living Things Respond to Stimuli Living • External stimuli pick up information from our senses • Vision, hearing, touch, taste, and smell • Allows us to respond to our external environment • Internal stimuli perceived by receptors for: • Stretch, temperature, pain, and various chemicals • Allows us to respond to our internal environment 12 Living things maintain homeostasis Living What is homeostasis? Maintaining a Maintaining constant internal environment environment Automatic Automatic adjustments made by the body or the cell the 13 Living Things Acquire Energy and Materials Materials Metabolism All reactions taking place in an organism Energy The ability to do work Ultimate source is the sun Flows one way through the ecosystem Much lost as heat Materials Building blocks of organisms As long as decomposers help out materials recycle through the As ecosystem ecosystem 14 15 15 Living things grow, reproduce, and evolve evolve DNA Molecule of heredity Blueprint for life Passed on from Passed parents to offspring parents Mutations produce Mutations variety variety Natural selection Natural allows for the development of new species over time species 16 Taxonomy Taxonomy • Domains: • Bacteria • Prokaryotic • Simple single cells • Variety of metabolisms Variety and habitats and • Archaea • Prokaryotic • Simple single cells • Molecular differences Molecular from typical Bacteria from • Usually live in extreme Usually environments environments • Eukarya • Eukaryotic • Complex cells with a Complex nucleus and many membrane bound organelles organelles 17 • Protista • • • Eukarya Kingdoms Eukarya • Single cells Many ways to obtains energy Protozoa and Algae Animalia • Multicellular • Obtain energy by ingestion • Plants • Fungi • • • • • Single cells or multicellular Obtain energy by absorption Molds, mushrooms, yeast 18 Multicellular Multicellular Obtain energy by Obtain photosynthesis photosynthesis Atoms and Life Atoms What is an atom? Fundamental units of Fundamental matter matter Consist of subatomic Consist particles particles Protons Neutrons Electrons 19 Atomic terms you need to know! know! Atomic symbol Shorthand to represent the atom’s name Atomic number Number of protons in the atom’s nucleus • Atomic mass – Number of protons and neutrons in the atom’s nucleus 20 Determining the Number of Subatomic Particles Particles • C=Carbon atomic # 6 atomic mass 12 • O=Oxygen atomic # 8 atomic mass 16 • P=Phosphorus atomic # 15 atomic mass 31 • Ca=Calcium atomic # 20 atomic mass 40 21 Electron Configurations Electron 22 Molecules and Bonding Molecules • Molecule – Two or more atoms held Two together by the interactions of electrons in their outer shell shell • Ionic Bonding – – Atoms lose or gain Atoms electrons to form charged ions ions Opposite charged ions Opposite attract 23 23 Molecules and bonding Molecules • Covalent Bond – – – Atoms share electrons to Atoms bond together bond Stronger than ionic bonds Most biological molecules Most formed from covalent bonds formed • Nonpolar covalent bond – Equal sharing of electrons • Polar covalent bond – Unequal sharing of electrons 24 Molecules and bonding Molecules • Hydrogen bonding – Due to polar nature of Due water molecules water – Partially negatively Partially charged oxygen on one water molecule is attracted to partially positive hydrogen on a different water molecule different 25 Water is necessary for life! Water • Universal Solvent – Good at dissolving substances • Cohesion – – Water molecules stick together Create surface tension • Withstand Temperature Changes – Large range of temperatures for Large liquid water liquid 26 The pH Scale The • Acid: More H+ than OH– Substance that releases H+ is considered acidic • Base: More OH- than H+ – – Substance that release OHSubstance that removes H+ • Log Scale – Each unit represents a ten fold change in H+ concentration 27 Biological Molecules Biological • Inorganic Molecules – – – Basis for nonliving molecules Still important to living organisms Cannot have C and H in them at the same time • Organic Molecules – Basis for living molecules – Must have C and H in them at the same time – Usually also have O, N, P, and S in them 28 Functional Groups Functional 29 Dehydration Synthesis Dehydration – – Monomer • Small subunit organic molecule Polymer • Macromolecule • Large organic molecule formed when many monomers join • Formed by dehydration synthesis – Remove OH from one monomer and H from another to join them Remove together together 30 Hydrolysis Hydrolysis • Hydrolysis – Water splitting – Water is split and the bond in the polymer is broken when Water the OH and H are added to it the – Monomers produced 31 What are Carbohydrates? What • Function – Quick energy production – Some are structural • Basic Formula – Monomer formula: Monomer (CH2O)n (CH 32 Disaccharides Disaccharides • Maltose – Glucose + glucose • Sucrose – Glucose + fructose • Lactose – Glucose + galactose 33 Polysaccharides of Glucose Polysaccharides • • Cellulose vs. Chitin – Both long glucose chains – Bonded monomers not Bonded easily broken easily – Not used for energy; used Not for structure for – Cellulose is fiber in plants Cellulose (cell wall) (cell – Chitin is exoskeleton in Chitin animals (insects, crabs, and lobsters) and Starch vs. Glycogen – – – – Both long glucose chains Both energy storage Starch found in plants Starch Glycogen found in animals 34 The Lipids The • Function – – – – Long term energy storage Insulation / Padding Structure Chemical messages • Lipid Diversity – – – – Triglycerides Phospholipids Waxes Steroids 35 Triglycerides Triglycerides • Function – Long term energy Long storage storage • Structure – – – Glycerol + 3 fatty acids Joined by dehydrations Joined synthesis synthesis Broken down by Broken hydrolysis hydrolysis 36 Saturated vs. Unsaturated Fats Saturated • Saturated – – – • All single bonds between carbons in fatty acid chains Saturated with hydrogen Solid at room temperature Unsaturated – – – One or more double bonds between carbons in fatty acid chains Less hydrogen required Liquid at room temperature 37 Wax Wax • Wax – Highly saturated and Highly solid at normal outdoor temperature temperature – Waterproof coating for Waterproof plants and animals plants – Cannot be digested by Cannot most animals most 38 Phospholipids Phospholipids • Phosopholipids – – – – Mixed up molecule Hydrophobic end Hydrophilic end Forms a phospholipid bilayer which is the Forms backbone of cell membranes backbone 39 Steroids Steroids • Steroids – No fatty acids – All composed of four All fused carbon rings fused – Many functions • Cholesterol stabilizes Cholesterol animal cell membranes animal • Testosterone and Testosterone estrogen are sex hormones hormones 40 Proteins Proteins • Function – – – Many roles in cells and Many organisms organisms Structural Enzymatic • Structure – – – Made by joining amino Made acids acids R group makes each amino group acid unique acid 20 biologically active amino 20 acids acids 41 Joining Amino Acids to Make a Protein Protein • Dehydration Synthesis • • • • OH removed from carboxyl end of one amino acid H removed from amino end of adjacent amino acid OH + H forms water and the two amino acids bond Bond called peptide bond 42 • Primary – • Order of amino acids in polypeptide chain Secondary – H-bonds between amino acids in the polypeptide chain cause folding and twisting • • Alpha helix or Beta pleated sheet Tertiary – – • Levels of Protein Structure Levels R group interactions bend and twist polypeptide into a globular shape Function dependent on shape if shape changes protein cannot function: denaturation Quaternary – – Only in SOME proteins Formed when more than one polypeptide chain join and work together 43 Nucleotides and Nucleic Acids Nucleotides • Nucleotide (monomer) – – Many different kinds with different function All have sugar, nitrogen containing base, and at least one phosphate All group group • Nucleic Acid (polymer) – – DNA (deoxyribonucleic acid) blueprint for life, instructions for making DNA proteins proteins RNA (ribonucleic acid) copy of DNA used to make protein 44 ...
View Full Document

Ask a homework question - tutors are online