BIO 101 1st EditionExam #1 Study Guide Chapters 1-5, & 7Lecture 1 (August 22)Biology, the Study of LifeUnifying Themes of Biology, focus on Cell Theory1. Life is organized on many structural levels- increased complexity as you move up levels2. Emergent properties- new properties emerge when you move up in complexity3. Cellular basis of life- cell theorya. All living things are made of cellsb. All cells come from other cells4. Heritable informationa. DNA is the genetic information in cellsb. The information in DNA flows in 2 waysi. Parentoffspringii. DNARNAproteinsThe study of how DNA is passed to offspring is called genetics.5. Correlation of structure and function- what a molecule looks like determines what it can do6. Unity in diversity- all living thing share certain traits, like a genetic code.Lecture 2 (August 27)Atoms, Molecules and Chemical BondsAtomic number and atomic mass- how they are symbolized, and how to determine the number of protons, neutrons and electrons from itAtomic number is the number of protons in an atom. Atomic mass is the number of protons and neutrons in an atom (how much the atom weighs). Ex: 12 superscript (represents atomic mass)C 6 subscript (represents atomic number)Protons= determined by subscript. Neutrons= Mass-atomic numberElectrons= same as protonsValence ElectronsValence electrons are the number of electrons needed to fill the outermost shell. This number represents the number of covalent bonds the element must form to be stable.For example, Hydrogen has only one electron in its outer shell. It would need another electron to fill its shell, so Hydrogen would need to form one covalent bond to be stable.BIO 101 1st EditionThe Chemical behavior of atoms depends on the number of bonds it needs to form. The valences of the 4 major elements (H, O, N, C) are important to all living things.element valenceH 1O 2N 3C 4Strong Bonds- what is the difference between a covalent and ionic bond? What is the difference between polar and nonpolar covalent bonds and how does it affect the behavior of the molecules formed?Covalent bonds are chemical bonds formed by sharing electronsIonic bonds are chemical bonds formed by the attraction between two atoms, and then a complete transfer of electrons from a donor atom to an acceptor atom.Nonpolar covalent bond- 2 atoms share a pair of electrons equally; the atoms have similar or identical electronegativityPolar covalent bond- 2 atoms share electrons unequally; one atom has a greater electronegativity, which leaves the other atom a little bit positively chargedWeak Bonds- hydrogen and hydrophobicHydrogen bond- a weak charge attraction between a partially (+)H atom of one molecule and a partially (-) atom of another molecule. There is no electron sharing or transfer, with a 1/20 strength of a covalent bond.Hydrophobic bond- tendency of nonpolar molecules to avoid H2O, which is a polar substance, and thus associate with each otherWhat is a hydrogen bond? Use water as an example; be able to draw a picture with an arrow showing the position of the hydrogen bond. A hydrogen bond is a weak charge attraction between a partially (+)H atom of one molecule and a partially (-) atom of another moleculeWhat does electronegativity mean?Electronegativity is the ability to attract electrons.How does polarity affect the behavior of molecules?If a bond is polar, then one atom in the bond, the one that “hogs” the shared electrons, is a little bit negatively charged. That leaves the other atom a little bit positively charged.BIO 101 1st EditionLecture 3 (August 29)Water (H2O)What are the unique characteristics of water? What are examples of the importance ofthese characteristics in living systems?1. High Specific Heat- amount of heat required to increase the temperature of a substance by 1 degree C. a. With H2O, heat goes first to break H-bonds; little change in temperatureb. If it takes out heat, H-bonds form (releasing heat) again, there is little change in temperature.Most living organisms are made up of mostly water, and so it helps organisms resist dramatic changes in temperature. It also helps stabilize ocean temperature, protecting marine organisms.2. Water expands when H freezes (ice floats on liquid water)a. H2O is one of only a few substances where the solid form is less dense than the liquid formsb. In liquid H2O, H-bonds form and break as the molecules move around.c. When they reach 0 degrees C, the molecules are no longer moving fastenough to break the H-bonds, and they become locked into a crystal lattice, where each H2O is bonded to the maximum number of partners held father apart from each other. 3. Water is the Biological Solventa. H2O is the solvent in living organismsb. The cell is like a tiny drop of H2O with many molecules (solutes) dissolved in itc. H2O is a good solvent for charged or polar substances, but nonpolar substances do not dissolve in H2O, because polar and nonpolar substances do not mixWhat is it about water that causes most of its unusual properties?The unusual behavior of water is due to its hydrogen bonding. Water is a polar molecule because of the polar covalent bonds between O and H. Water molecules areattracted to one another due to charge attraction. Properties of Water Solution (Molarity and pH). Know the definitions and be able to apply to simple problems. Know how to make a solution of a given Molarity, know how to figure out the number of molecules in a solution of given molarity (review sample problems on BlackBoard). Be able to determine pH given either the [H+] or the [OH-]Mole= number of grams of a substance equal to its molecular weight (in Daltons)Molar= number of moles of a solute in 1 liter of solution; the concentrationpH= (-)log[H+]pH + pOH= 14[H+]+[OH-]= 10^(-14)One unit change in pH is a 10-fold change in [H+]. For example, if the pH goes from 6 to 7, there is a 10% change.BIO 101 1st EditionLecture 4 (September 3)Carbon and Molecular DiversityKnow some reasons why Carbon is the element of life.Carbon is small, and forms strong bonds (4 covalent bonds). It is versatile in bonding; can bond to other carbon atoms or several other elements. It can form large complex and diverse molecules, which is important for living things. It can be used to make many kids of molecules that have different functions.Terms: organic and hydrocarbon. What is a hydrocarbon and why are these molecules nonpolar? Organic- molecules that contain carbonHydrocarbon-