Chapter 1 Biology Exam Study Guide

2013-2014 Biology Semester 1 FinalExam Study Guide Answer KeyChapter 1 Biology in the 21st Century1. What is biology the study of? Biology is thestudy of life.2. What are the 4 characteristics of life? 1. Allorganisms are made up of one or more cells.2. All organisms need a source of energy fortheir life processes. 3. All organisms mustrespond to their environment. 4. Members ofa species must have the ability to reproduceand develop.3. How are structure and function related inbiology? Structure and function are related atthe level of chemicals in cells. Different typesof cells have different functions that depend ontheir specialized structures (i.e. brain cells havebranches that receive info from other cells).Structure and function are also related on thelevel of the organism (i.e. ducks have webbedfeet to swim and walk).4. What is homeostasis? Give an example ofhow you maintain homeostasis. Homeostasis isthe maintenance of constant internalconditions. Sweating when you are hot andshivering when you are cold are examples.5. List and explain the general steps of thescientific method. Observation, Hypothesis,Experiment, Collect data, Evaluate results,Draw a conclusion, and Retest.6. What are independent and dependentvariables? (Explain) A variable is a factor in theexperiment that is being tested.The independent variable is the factor that iscontrolled/manipulated by the experimenter.The dependent variable is the factor that isbeing observed/measured.7. What are constants and controls?The experimenter makes a special effort tokeep other factors constant (the same) so thatthey will not affect the outcome. Those factorsare called control variables.8. Sugar dissolves in, or mixes completely with,water. The solubility of a substance in water isdetermined by measuring the maximum amountof the substance that dissolves in a givenamount of water at a given temperature.HYPOTHESIS: The solubility of sugar in waterincreases as the temperature of the waterdecreases. Identify the independent anddependent variables. Ind. var – temp. of waterDep. var – solubility of sugar9 An electromagnet can be made by wrappinginsulated wire around an iron nail andconnecting the ends of the wire to a 6-voltbattery. HYPOTHESIS: Increasing the number ofcoils of wire wrapped around the nail increasesthe strength of the electromagnet, as measuredby the number of paper clips the magnet canpick up. Identify the independent anddependent variables. Ind. var – number of coilswrapped around nail; Dep. var – strength ofelectromagnetChapter 2 Chemistry of Life1. What is the difference between a covalentbond and an ionic bond? A covalent bondinvolves the sharing of electrons while anionic bond requires the transfer ofelectrons.2. What are the 4 properties of water? Wateris a polar molecule. It has hydrogen bondsthat are responsible for water’s highspecific heat, cohesion, and adhesion.3. Is water polar or non-polar, and why is thisimportant? Water is a polar molecule; thisis important because it allows water tohave charged regions which in turn allowshydrogen bonds to form.4. What is adhesion? (give an example)Adhesion is the attraction among moleculesof different substances (i.e. watermolecules sticking to the sides of a glass).5. What is cohesion? (give an example)Cohesion is the attraction among moleculesof the same substance (i.e. water sticking towater).

6. Why is the fact that water has a high specificheat important? This property is importantin cells because processes that produceusable chemical energy in cells release a lotof heat; water absorbs the heat, whichhelps to regulate cell temperatures andmaintain homeostasis.7. What is a monomer? A monomer is eachsubunit in a complete molecule. What is apolymer? A polymer is a large molecule, ormacromolecule, made of many monomersbonded together.8. Fill in the chart below.PolymerMonomer FunctionFoodsCarbohydrateLipidProteinNucleic acidsGlucoseGlycerolAmino acidsNucleotidesWhat thebody uses itfor?What types offoods do youeat to get it?Brokendown toprovideusableenergy tocells.Brokendown toprovideusableenergy tocells; someare parts ofa cell’sstructure.Formovement,eyesight, ordigestion.Sugars andstarches (i.e.cereal,pasta,sugars, etc.Providedetailedinstructionsfor how tobuildproteins.Fats and oils(i.e. Meat,butter, oliveoil, peanutoil, etc.)Your bodymakes 12 ofthe aminoacids. Otherscome frommeat, beans,and nuts.DNA andRNA9. 2HO2 H2 O2 Explain why this is achemical reaction; label the reactants andthe products of this reaction. 2HO2 is thereactant and H2 O2 are the reactants. Thisis a chemical reaction in which a compoundis being broken apart.10. What is a catalyst? (give an example) Acatalyst is a substance that decreases theactivation energy needed to start achemical reaction. It also increases the rateof the chemical reaction.11. What is an enzyme? (give an example)Enzymes are catalysts for chemicalreactions in living things (i.e. amylase is anenzyme in saliva that breaks down starch).12. Use the diagram above to explain how anenzyme works.Substrates bind to an enzyme at certain placescalled “active sites”. The enzyme bringssubstrates together (or breaks them apart) andweakens their bonds. The catalyzed reactionforms two products that are released from theenzyme.Chapter 3 Cells and Organelles Cell Theory – list the 3 parts of the celltheoryAll organisms are made of cells. All existingcells are produced by other living cells. Thecell is the most basic unit of life. Two types of Cells – describe thedifference between prokaryotic andeukaryotic cellsProkaryotic cells do not have a nucleus orother membrane-bound organelles. Theyconsist of a cell membrane, cytoplasm, andDNA. All single-celled organisms areprokaryotic (i.e. bacteria)Eukaryotic cells have a nucleus and othermembrane-bound organelles. The geneticinformation (DNA) is inside the nucleus.Eukaryotes may be multi-cellular or singlecelled organisms (i.e. plant & animal cells).

Organelles :o What are they? Structuresspecialized to perform distinctprocesses within a cell (i.e. nucleusprotects a cell’s DNA).o Describe the functions of thefollowing organelles and be ableto pick them out of a diagram: Nucleus – the storehouse for most of the genetic information (DNA). Servesto protect DNA; the nucleolus is in thenucleus.Mitochondria – bean-shapedorganelle that has two membranes;responsible for supplying energy to thecell.Lysosomes – membrane boundorganelles that contain enzymes. Theydefend a cell from invading viruses andbacteria; they also break down damaged or worn-out cell parts.Chloroplast – organelle found inplant cells that carry out the process ofphotosynthesis by converting carbondioxide, water, and solar energy intoglucose and oxygen.Ribosomes – tiny organelles that linkamino acids together to form proteins.Ribosomes are either on the rough ERor in the cytoplasm.Vesicles – small membrane boundsacs that divide some materials fromthe rest of the cytoplasm and transportthese materials from place to placewithin the cell.Golgi Apparatus – closely layeredstacks of membrane-enclosed spacesthat process, sort, and deliver proteins.Endoplasmic Reticulum (ER) – aninterconnected network of thin, foldedmembranes; the production of lipidsand proteins occurs in the ER. Thereare two types: smooth and rough; therough ER is studded with ribosomes.Cell membrane – consists of adouble layer of phospholipidsinterspersed with a variety of othermolecules. The cell membrane forms aboundary between the cell and theoutside environment and controls thepassage of materials into and out of acell. Cell wall – a rigid layer that givesprotection, support, and shape to plantcells.Phospholipid Bilayer What is it made of (which parts are polarand which are non-polar)? A phospholipid is composed of three basic parts: acharged phosphate group, glycerol, and twofatty acid chains. The head is polar and thefatty acids chains are nonpolar. What is selective permeability? The cellmembrane has the property of selectivepermeability which means it allows some,but not all, materials to cross.Passive Transport – what is it? The movement ofmolecules across a cell membrane without energyinput from the cell. Diffusion – What is it? The movement ofmolecules in a fluid or gas from aregion of higher concentration to aregion of lower concentration. What is a concentrationgradient? The difference in theconcentration of a substance fromone location to another. Osmosis – What is it? The diffusion of water. In what direction does the watermove in the following solutions:o hypotonic – into the cello isotonic – into and out ofothe cell at an equal ratehypertonic – out of thecell Facilitated Diffusion – What is it? The diffusion of molecules across a membranethrough transport proteins.How does it work? Transportproteins make it easier formolecules to enter or exit a cell.This is still a form of passivetransport because molecules movedown a concentration gradient.

Active Transport – what is it? A process in whicha molecule is driven across a membrane from aregion of lower concentration to a region of higherconcentration. Endocytosis –o What is it? The (entrance) processof taking liquids or fairly largemolecules into a cell by engulfingthem in a membrane.o Phagocytosis – a type ofendocytosis in which the cellmembrane engulfs large particles. Exocytosis –o What is it? The release (exit) ofsubstances out of a cell by thefusion of a vesicle with themembrane.o How does it work? During thisprocess, a vesicle forms aroundmaterials to be sent out of the cell.The vesicle then moves toward thecell’s surface where it fuses withthe membrane and lets go of itscontents.Chapter 4 Cells and Energy1. What is ATP? Adenosine triphosphate is amolecule that transfers energy from thebreakdown of food molecules to cellprocesses. Energy is transferred when achemical bond is broken by releasing aphosphate group and energy is released.2. What is the difference between theenergy stored in food and the energy inATP? Food molecules store chemicalenergy in their bonds. Food is broken downinto smaller molecules that are brokendown further to transfer this energy to ATP.3. What is the purpose of cellularrespiration? The purpose of cellularrespiration is to release chemical energyfrom sugars and other carbon-basedmolecules to make ATP when oxygen ispresent. This is an aerobic process (requiresoxygen).4. Where does cellular respiration occur? Inthe mitochondria because they make mostof a cell’s ATP.5. What is aerobic respiration? (include theadvantages and disadvantages) Aerobicrespiration is a process that requiresoxygen to take place. Cellular respiration isan aerobic process.6. What is anaerobic respiration? (includethe advantages and disadvantages)Anaerobic respiration is a process that doesnot require oxygen to take place. Glycolysisand fermentation are anaerobic process.Match the following processes with thestatements below:a. Glycolysisc. Fermentationb. Kreb’s cycled. Electron Transport chain7. Which process(es) are aerobic? B & D8. Which process(es) are anaerobic? A & C9. Which process(es) starts with sugar andends with pyruvate? A10. Which process(es) allows glycolysis tocontinue if oxygen is not readilyavailable? C11. Which process(es) produces the mostATP? D12. Which process(es) has the products of:2 ATP, 6 CO2, 8 NADH, and 2 FADH? B13. Which process produces Lactic Acid? C14. Which process is the first step of cellularrespiration? B15. What are the products of glycolysis? 2ATP & two pyruvates (three-carbonmolecules)16. How many ATPs can be produced by theelectron transport chain? 34