Study Guide for Exam 1
Study Guide for Exam 1 111-567
Popular in Introductory Biology I
verified elite notetaker
Popular in Biology
This 14 page Study Guide was uploaded by Emma Notetaker on Sunday September 18, 2016. The Study Guide belongs to 111-567 at Texas A&M University taught by Andrew Tag in Fall 2016. Since its upload, it has received 228 views. For similar materials see Introductory Biology I in Biology at Texas A&M University.
Reviews for Study Guide for Exam 1
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 09/18/16
CHAPTER ONE There is much organization in life. Levels of organization: Subatomic particles > atoms > organelles > cells > tissues > organs > organ systems > organisms > populations > communities > ecosystems > biomes All life: ● Reproduces ● Processes energy/acquires nutrients ● Produces/eliminates wastes ● Responds to stimuli in order to maintain homeostasis With higher levels of organization come emergent properties ● example carbon, hydrogen, and oxygen are elements with their own unique properties but when they are bonded together they can form a carbohydrate, which has new traits, properties, and functions Reductionism reduces complexities into smaller components in order to understand how it interacts ● Example one might research nucleotides and understand how the individual unit works to further understand how DNA works Systems biology is a combination of components that work together ● Constructs behavioral norms for the whole body ● Can be used to predict results of reactions All cells have DNA and a membrane, but there are two domains of cells Prokarya ● No nucleus ● No membrane bound organelles ● Usually have a cell wall ● Sometimes have flagella ● Bacteria and Archaea Eukarya ● Has a nucleus that directs cell operations ● Has membrane bound organelles ● Are larger comparatively to prokaryotes ● Animalia and plant cells Viruses are not alive and therefore not cells ● Viruses need host cells in order to replicate ● Insert DNA through protein plasmids DNA is a cell’s means of heredity and replication ● Each DNA molecule is a double helix ● DNA is a chain of subunits called nucleotides ○ Four different kinds of nucleotides involved in the composition of DNA ● Cells divide and become ‘daughter cells’ ○ Evolution is entirely dependent on the passage of DNA ● Entire set of DNA is called the genome An organism’s adaptations are a product of evolution ● Organisms do not evolve, populations do ● Selective pressures make a set of traits more desirable and therefore become more prevalent in the gene pool ● Example trees turn a dark color because of carbon emissions. White moths are easily spotted by predators and do not live long enough to reproduce (because they were eaten). The less easily spotted darker colored moths then live longer, reproduce more, and rule the gene pool. Cells are the smallest unit of life that can still perform all of life’s functions ● All actions and functions of an organism mirror that of a cell Organisms are open systems ● Energy is exchanged with the environment that organism is in ● All living things are dependent on energy and nutrient cycling ● All energy a cell uses flows from the sun Regulatory systems function to maintain homeostasis ● Body uses enzymes to speed up reactions ● Many biological processes are self regulating through feedback loops ○ Negative feedback an inhibition that slows a process ■ Ex you eat a bunch of food. Blood glucose levels rise. The body secretes insulin and circulates it through the bloodstream. Blood sugar levels decrease. ○ Positive feedback speeds up processes ■ Ex contractions in pregnancy start off slow and weak and keep going, becoming more frequent and more powerful All life shares (REMEMBER VIRUSES ARE NOT ALIVE): ● DNA ● mRNA ● tRNA ● Ribosomes Diversity is accounted for by evolutionary processes ● Theories stem from Darwin’s Origin of Species ● Main points: descent with modification (genetics) and natural selection Natural Selection is the driving force of adaptations and evolution ● Environments dictate what fitness looks like ● Selective pressures from the environment determine which traits become more frequent What is necessary for evolution: ● Population with varied traits (genes) ● Elimination of individuals with specific traits ● Reproduction of survivors ● Selected trait that increases in frequency ● STERILE INDIVIDUALS HAVE NO ROLE IN EVOLUTION EVEN IF THEY ARE THE MOST FIT Populations evolve not individuals Populations evolve not individuals Populations evolve not individuals Populations evolve not individuals Discovery based science describing/ analyzing observations ● Done through natural structures ● Described quantitatively and qualitatively Hypothesis based science develops a specific question that is testable and falsifiable Genes are encoded strands of DNA made of four nucleotides ● The order of nucleotides determines traits ● All genes/DNA are made of the same four subunits Genes control protein production through gene expression ● DNA is transcribed by RNA and then the RNA regulates the production ● Proteins are made by: a. Transcription of DNA the cell splits the DNA and uses RNA to make a copy of the sequence ■ RNA uses three of the same nucleotides as DNA, but uses U instead of T b. Translation cell uses the information from the mRNA to form a protein c. Protein folding the amino chain folds into a specific protein with a three dimensional structure Life requires the transfer and transformation of energy ● Almost all cell actions require energy ● All energy flows from the sun ○ Cells either produce their own energy (photosynthesis) ○ Consume energy from a plant ○ Decompose a dead organism and release energy The three broadest classifications of life are 1. Bacteria 2. Archaea 3. Eukaryotes (plantae, fungi, and animalia) All life with a common ancestor has the same basic structure but evolved to fit necessary function of an organism in order to reach fitness ● A population with a common ancestor can splinter and two groups could then live in two different environments. Each environment could have its own selective pressures and therefore shape the two groups into two different evolutionary groups CHAPTER TWO AND THREE Keep going; I believe in you. Do this for Harambe. Organisms are all made of matter ● They take up space and they have mass ● Made of elements ○ Compounds are substances made of two or more different elements ○ Compounds have characteristics different from the elements they are made of Some elements are essential for life 1. Carbon 2. Hydrogen 3. Oxygen 4. Nitrogen Some trace elements are essential in trace amounts ● Example iron is necessary only in small amounts but is that allows red blood cells to carry oxygen Element’s properties depend on the structure of the atom Subatomic particles: ● Neutrons no charge ● Protons positively charged ● Elections negatively charged orbits nucleus All atoms differ in the number of sub atomic particles ● Atomic number = number of protons ● Mass number = protons + neutrons ● Electrons do not weigh much at all Isotopes differ in number of neutrons in the nucleus ● Most are stable ● Some are radioactive ○ Decay at a rapid rate ○ Scientists use the radioactive isotopes as markers to tell how old fossils are ● Isotopes can also be used to mark cells to study DNA synthesis and in medical scans to screen for cancer ● Used to irradiate food to eliminate disease and make the food have a longer shelf life ○ FOOD IS NOT RADIOACTIVE The behavior of an atom mostly depends on its outermost shell ● Called valence shell ● The unpaired electrons on the shell are called valence electrons ○ The electrons bond with electrons of other atoms and form molecular structures Because electrons orbit the nucleus so rapidly, we never actually know where the electron is ● The space where electrons are 90% of the time is called the orbital Compounds are made of two or more different molecules ● H2 is a pure element ○ Even though two elements are present, they are the same element ● H2O is a molecule ○ Composed of two different elements and chemically bonded together Electronegativity is the attraction of a particular atom for the electrons of a covalent bond ● Covalent bonds are strong bonds and share a pair of electrons ○ Can be written so the HH represents H2 with a covalent bond joining them together ● This is what differentiates polar from nonpolar bonds ○ Polar covalent bond is a bond that does not share the electron equally ■ One atom pulls the electron closer to its nucleus ■ Atoms involved in bond will have partial charges ■ Ex in water, oxygen pulls the electron of hydrogen much closer to its nucleus than hydrogen tries to ○ Non polar covalent bond is a bond that shares the electron equally ■ Usually composed of two of the same elements ● You can use the periodic table to see trends and guess the atom’s electronegativity more ↑less Less →→→→→→→→ More electronegative ● Fluorine is the most electronegative Ionic bond is a bond where one atom is so electronegative that it strips another atom of an electron completely ● This is a strong bond, but if it is reacted with a polar solution like water, the solution weakens the bonds ● This then makes one atom (the one that has an extra electron) negative and the other (the one that lost the electron) positive ● Because these atoms now have negative charges, they are attracted to each other ● The products are now called ions ● Positively charged ions are called cations (tip to remember, cats have paws (paws)itive) ● Negatively charged ions are called anions ● THE TRANSFER OF THE ELECTRON IS NOT WHAT CAUSES THE BOND, THE ENSUING OPPOSITE CHARGES CAUSE THE BOND Hydrogen bonds are weak chemical bonds ● They can be easily changed or reversed ● DNA is held together by hydrogen bonds Van der Waals interactions are actually pretty flipping cool ● Electrons are not evenly distributed, so this causes areas of the atom to be positive or negative temporarily ● This creates temporary attraction between the positivity of one place and the negativity of another area allowing atoms to “stick together” ● These interactions are weak independently, but thousands of them can be happening at the same time and make a strong hold ● Geckos crawling everywhere Making chemical bonds and breaking chemical bonds creates chemical reactions ● Reactants → products ● 2H2 + O2 → 2H2O ● Reactions cannot create or destroy atoms but redistribute electrons ● When reactions are in equilibrium, the reaction goes back and forth at equal rates ○ Also called “stable” Water supports all life ● Biological medium of Earth ● All living things require water and most are made mainly of it ● Earth is only habitable because of water ● Water is polar and can form hydrogen bonds because of it ○ Ions are hydrophilic ■ Water loving ■ Partially charged ○ Fats and oils are hydrophobic ■ Water fearing ■ They are non charged and nonpolar Emergent properties of water: 1. Cohesive and adhesive properties a. Cohesion water molecules stick to each other b. Adhesion water molecules stick to other surfaces and substances c. This is also the reason water has such a high surface tension 2. Ability to moderate temperature a. Water absorbs heat from air that is warm and releases the warmth it absorbed when the air is cold 3. Water expands when it freezes a. Most substances become more dense when it freezes b. Water becomes less dense because the molecules can no longer constantly create and break bonds and it frozen into a lattice structure c. This is what allows ice to float on top of water i. When ice freezes on top of water, it insulates the water underneath and protects it and its contents ii. This allows life to continue when it freezes 4. Versatility as a solvent “universal solvent” a. Because water is polar it can dissolve a lot of solutes Water also has a high specific heat, which is the amount of heat (energy) that must be absorbed in order to raise one gram of water by 1 degree Celsius ● Heat is released to form bonds and heat is released in order to break bonds Temperature vs. heat ● Heat is total kinetic energy ○ The movement causes thermal energy ● Temperature is the average amount of kinetic energy Heat of vaporization the amount of energy that must be absorbed bor 1g of water to become vapor ● Water has a high heat of vaporization ● Hydrogen bonds must break before water can become vapor ● This helps moderate the earth’s climate Mixture of two or more substances is called a solution ● A solute is what is being dissolved ● The solvent is what the solute is being dissolved in ● Example if you put salt in water and stirred it until it dissolved, the solute would be the salt and the solvent would be the water When water is the solvent in a solution, it is called an aqueous solution ● In these solutions hydration shells from around the solute ● Creates a kind of cloud around the introduced solute Base a substance that reduces the hydrogen ion concentration ● pH 814 Acid a substance that adds hydrogen ions into a solution ● pH 16 ● Removed hydroxide ions Buffer a substance that minimize the fluctuation in pH ● Helps cells maintain stability and homeostasis ● Made of an acid/ base pair CHAPTER FOUR WE ARE MOSTLY DONE! YOU CAN DO THIS! JUST READ IT AND MAKE A STINKING A! Organic chemistry is the study of compounds containing carbon ● Carbon and the fact that is has four valence electrons is responsible for much of life’s diversity ● Electron configuration determines an atom’s chemical characteristics ● Because carbon has four valence electrons, it can bond with a bunch of other atoms and create complex bonds Carbon, hydrogen, oxygen, and nitrogen are the main components of organic molecules Carbon chains form the skeletons or backbones of most organic molecules ● These vary in length and shape ● Important to complexity and diversity of organic molecules Hydrocarbons are molecules consisting only of hydrogen and carbon ● All available electrons bond themselves to a carbon ● This is the main component of petroleum ● Always hydrophobic and will not dissolve in water Isomers are compounds that have the same chemical formula but differ in structure of atoms and different functions Three kinds: 1. Structural isomers differ in arrangements of atoms and location of double bonds a. 2. Cistrans isomers a. Also called geometric isomers b. Differ in spatial relationship that is caused by double bonds inflexibility i. Atoms can rotate on a single bond but are immobile in a double bond c. 3. Enantiomers mirror images a. Caused by an asymmetric carbon b. Akin to a left and right hand c. FUNCTIONAL GROUPS: NAME FORMULA STRUCTURE P/NP MOLECULES MISC. Carboxyl COOH Polar Amino acids Acts as an Fatty acids acid Aldehyde COH Polar Sugar Hydroxyl OH or HO Polar Alcohol Good solvent Methyl CH3 Non polar Fats/lipids Affects functions of hormones Phosphate OPO32 Polar Cell Contributes a membranes neg charge Sulfhydryl SH or HS Polar Proteins/amin Can stabilize o acids proteins Carbonyl OH Polar Sugars Also called a group ketone Acts as an acid Base Amino NH2 Polar Amino acids Acts as a base Water has the ability to form four hydrogen bonds with other molecules ● Hydrogen has a partial charge (+) ● Oxygen has two partial charges () Moles are an exact number of molecules (6.02 x 10^23) ● A mole’s mass is determined by the the atomic mass of the molecule ATP is the source of energy for cells ● Is made of three phosphates and a bunch of oxygens ● It is inorganic ● When it is used for energy, it becomes ADP Water can dissociate into hydronium and hydroxide ions ● Ions are reactive after this process ● This reaction is reversible ● In pure water, these ions are present, but at very low levels ○ Adding an acid increases the hydrogen ion concentration ○ Adding a base reduces the hydrogen ion concentration ● Adding strong acids/bases dissociates in water completely ○ Adding weak acids/bases the dissociation is partial and reversible [H+][OH] = 10^14, so if the pH is 8, then [H+]= 10^8 [OH] = 10^6 ● Most buffers are at pH 68 CHAPTER 5 MOMMA WE MADE IT Macromolecules are large molecule such as nucleic acids, proteins, and carbohydrates ● Polymers are constructed of monomers ● These monomers are joined together by covalent bonds and each monomer contributes a part of a water molecule (either OH or H) ○ Monomers are essentially building blocks ○ If you were making a beaded bracelet, each bead would be a monomer and the bracelet as a whole would be a polymer Hydrolysis is when a bond between monomers is broken down and releases a water molecule ● The components that each molecule contributed to make the bond are given back and they both have a component of water again Dehydration is where a water molecule is taken out and the bond is made ● Both monomers sacrifice their portion of the water molecule ● Water is produced ● A covalent bond is made Enzymes break down covalent bonds that form monomers from polymers and break down strings of bonds back into monomers Carbohydrates are sugars that provide energy and building blocks of structure ● Monomers monosaccharides ● Polymers polysaccharides ● Most common monosaccharide is glucose ○ Some sugars only differ in spatial construction ● Polysaccharides are macromolecules ○ Thousands can be joined by covalent bonds ● Plants and animals store energy through sugar storage ○ Plants store sugars as starch ■ These are granules inside plastids ■ Starch can be branched (amylopectin) or unbranched (amylose) ○ Animals store sugars in the liver and muscles as glycogen ● Ketoses have double bonds in the middle of the structure ● Aldehydes have carbon double bonds to oxygen Fats/ Lipids are not polymers but are large molecules that are formed by smaller subunits ● Lipids are insoluble in water ● Fatty acids are long carbon skeletons with carbon group on end ○ Rest of the chain is made of hydrocarbons ○ Three fatty acids formed together form the triglycerol Saturated vs unsaturated fats: ● Saturated fats have single bonds, whereas unsaturated fats have double bonds ● Saturated fats are solid at room temperature, whereas saturated fats are liquid oils Phospholipids, which make up the cell membrane, have two fatty acids attached to a triglycerol ● Joined to a phosphate group ● These have hydrophilic heads and hydrophobic tails Steroids are lipids made in carbon rings ● Example cholesterol Amino acids are organic molecules with an amino group and carboxyl ● Carboxyl acts as an acid ● Very diverse functions ○ Defense proteins ○ Structural ○ Transport ○ Messenger (hormones) ○ Storage ● Enzymes are one of these products and they speed up reactions and break down bonds ● Polypeptides are polymers of amino acids ○ Composes proteins ○ Aminos acts as bases ○ Even small changes in the primary shape can affect a protein’s shape and function ■ Can impede blood flow Protein structure determined by interactions responsible for secondary and tertiary shape ● Shape is formed during protein synthesis ● Environmental factors can unravel proteins and interfere with their development ○ pH, temperature, salt concentration ● Unraveling can be reversed through renaturation Chaperonins assist in folding proteins ● Keeps proteins in an environment that is good for synthesizing ● Creates a sort of capsule for it Nucleic acids form nucleotides, which make our genes! ● Two kinds of products DNA and RNA ○ DNA always stays in the nucleus of Eurkaryotes and the call of Prokaryotes ○ RNA copies the DNA and can leave the cell and send out messages ■ Responsible for protein synthesis
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'