Advanced Placement BIOLOGY

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2 Advanced Placement BIOLOGY

3 CHS Student Handbk

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5 There will nt be a secnd semester final exam fr students that take the AP Exam The New AP Bilgy Exam Design

6 Example f a Multiple Chice Questin 1. Tw flasks with identical medium cntaining nutrients and glucse are inculated with yeast cells that are capable f bth anaerbic and aerbic respiratin. Culture 1 is then sealed t prevent fresh air frm reaching the culture; culture 2 is lsely capped t permit air t reach the culture. Bth flasks are peridically shaken. Which f the fllwing best predicts which culture will cntain mre yeast cells after ne week, and mst accurately justifies that predictin? A.Culture 1, because fresh air is txic t yeast cells and will inhibit their grwth B.Culture 1, because fermentatin is a mre efficient metablic prcess than cellular respiratin C.Culture 2, because fresh air prvides essential nitrgen nutrients t the culture D.Culture 2, because xidative cellular respiratin is a mre efficient metablic prcess than fermentatin Examples f Shrt Free Respnse Questins 2. Currently, all living rganisms are classified int ne f three dmains: Bacteria, Archaea, and Eukarya. In a sentence r tw, prvide tw pieces f evidence that justify a cmmn rigin fr the three dmains 3. The activity rate f an enzyme was measured at varius temperatures based n the amunt f substrate, in micrmles, prduced per square meter f reactin surface per secnd. The table belw shws the data cllected. In tw r three sentences, indicate the nature f the relatinship between enzyme structure/functin and envirnment temperature that explains the data shwn in the table. Examples f a Grid-In Questin Requiring Calculatr Use 4. The data belw demnstrate the frequency f tasters and nn-tasters in an islated ppulatin at Hardy-Weinberg equilibrium. The allele fr nn-tasters is recessive Hw many f the tasters in the ppulatin are heterzygus fr tasting? Tasters Nn-tasters

7 Tips Fr Writing AP Exam Essays 1 DO s 1. The first thing that yu shuld d is t carefully read the questin. The secnd thing yu shuld d is read the questin, and the third thing yu shuld d is read the questin. Be sure that yu answer the questin that is asked and nly that questin, and that yu answer all parts f it. If yu are given a chice f parts t answer, chse carefully. Dn t answer all parts in that case. 2. Briefly utline the answer t avid cnfusin and disrganizatin. Pay clse attentin t the verbs used in the directins (such as describe, explain, cmpare", give evidence fr, graph, calculate, etc.) and be sure t fllw thse directins. Thinking ahead helps t avid scratchuts, asterisks, skipping arund, and rambling. 3. Write an essay. Outlines and diagrams, n matter hw elabrate and accurate, are nt essays and will nt get yu much, if any, credit by themselves. Exceptins: If yu are asked as a part f an essay n a lab t calculate a number, this part des nt require an essay, but be sure t shw hw yu gt yur answer (shw the frmulas yu are using and the values yu have inserted int thse frmulas); r, if yu are asked t draw a diagram in the questin, d s, but be sure t anntate it carefully and thrughly. 4. Define and/r explain the terms yu use. Say smething abut each f the imprtant terms that yu use. The AP Exam will nt ask fr a list f buzzwrds. Use high-level vcabulary but use it in cntext. 5. Answer the questin parts in the rder called fr and label them a, b, etc., as they are labeled in the questin. It is best nt t skip arund within the questin. The fur essay questins d nt have t be answered in any particular rder. The readers will find yur answer. Put the number in the bx at the tp f the page t make it easy t find yur answer. 6. Write clearly & neatly. It is flhardy t antagnize r cnfuse the reader with lusy penmanship. 7. G int detail that is n the subject and t the pint. Be sure t include the bvius (fr example, light is necessary fr phtsynthesis). Answer the questin thrughly. 8. If yu cannt remember a wrd exactly, take a sht at it--get as clse as yu can. Even if yu dn t remember the name fr a cncept, describe the cncept. 9. Use a ball pint pen with dark black ink. If it bleeds thrugh t the ther side f the paper, dn t write n the back f that page. That will make it make it easier fr the reader. 10. Remember that n detail is t small t be included as lng as it is t the pint. Be sure t include the bvius--mst pints are given fr the basics anyway. 11. If yu use a diagram, carefully label it (it will get n pints therwise) and place it in the text at the apprpriate place- -nt detached at the end. Be sure t refer t the diagram in yur essay. 12. Widen yur margins a little. This will make the essay easier fr mst flks t read. 13. Bring a watch t the exam s that yu can pace yurself. Yu have fur essays with abut 22 minutes fr each answer. The prctr will nt give yu time cues. 14. Understand that the exam is written t be hard. The natinal average fr the essay sectin will be under 50% crrect, that is less than 5 pints ut f a pssible 10 n each essay. It is very likely that yu will nt knw everything. This is expected, but yu will knw smething abut each essay, s relax and d the best yu can. Write thrugh answers.

8 15. If yu are asked t design r describe an experiment, include these things: a. hypthesis and/r predictins b. identify independent variable(s)--what treatments will yu apply c. identify dependent variable(s)--what will measure t see if the independent variable had an effect d. describe hw yu will measure the independent variable, AND why it will wrk in this case e. identify several variables t be cntrlled (VERY IMPORTANT) f. describe the rganism/materials/apparatus t be used g. describe what yu will actually d (hw will yu apply the treatment) h. describe hw the data will be graphed and analyzed i. state hw yu will draw a cnclusin (cmpare yur results t hyptheses & predictins) k. Yur experimental design needs t be at least theretically pssible and it is very imprtant that yur cnclusins/predictins be cnsistent with 1) the principles invlved and 2) with the way yu set up the experiment. Make sure the experiment is internally cnsistent 16. If yu are asked t draw a graph, include these things: a. set up the graph with the independent variable (manipulated variable) alng the x-axis and dependent variable (respnding variable) alng the y-axis. b. mark ff axes in equal (prprtinal) increments and label with prper units c. plt pints and attempt t sketch in the curve (line). d. if mre than ne curve is pltted, write a label n each curve (this is better than a legend) e. label each axis with the variable name and include the units in which it is measured (C. mm, etc f. give yur graph an apprpriate title (What is it shwing? Try: Y as a functin f X ). DON TS 1. Dn t waste time n backgrund infrmatin r a lng intrductin unless the questin calls fr histrical develpment r histrical significance. Answer the questin. 2. Dn t ramble--get t the pint, and dn t sht the bull--say what yu knw and g n t the next questin. Yu can always cme back if yu remember smething. 3. Dn t use a pencil, and dn t use a pen with an ink clr ther than black. Dn t use a felt-tip pen because the ink seeps thrugh the page and makes bth sides f the paper hard t read. Dn t scratch ut excessively. One r tw lines thrugh the unwanted wrd(s) shuld be sufficient, and dn t write mre than a very few wrds in the margin. Finally dn t write slppily. It is easy fr a grader t miss an imprtant wrd when he/she cannt read yur handwriting. 4. Dn t panic r get angry because yu are unfamiliar with the questin. Yu prbably have read r heard smething abut the subject--be calm and think. 5. Dn t wrry abut spelling every wrd perfectly r using exact grammar. These are nt a part f the standards the graders use. It is imprtant fr yu t knw, hwever, that very pr spelling and grammar will hurt yur chances. 6. There is n need t say the same thing twice. While intrductry paragraphs may be imprtant in English class, n the AP Exam they are a waste f valuable time. This als ges fr restating the questin. Dn t restate it, just answer it. 7. If given a chice f tw r mre tpics t write abut, understand that nly the first ne(s) yu write abut will cunt. Yu must make a chice and stick with it. If yu decide that yur first chice was a bad ne, then crss ut that part f the answer s the reader knws clearly which part yu wish t be cnsidered fr credit. 8. Dn t leave questins blank. Remember that each pint yu earn n an essay questin is the equivalent f tw crrect multiple chice questins, and there is n penalty fr a wrng guess, baad spelig; r bad grammar. Make an effrt n ever questin! Dn t Quit!

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11 Title Purpse Hypthesis Materials Prcedure Results/Data/Observatins Discussin/Cnclusin Critique Signature Adapted frm Snja Raynes, Turlck High Schl

12 EXAMPLES OF DATA TABLES Once the data are cllected, they must be rganized and summarized s that the scientist can determine if the hypthesis has been supprted r negated. Tables and graphs (als called 'figures') have tw primary functins. They are used t (1) help yu analyze and interpret yur results and (2) enhance the clarity with which yu present the wrk t a reader r viewer. They are als useful t display several dependent variables at the same time. Fr example, average pulse rate befre and after exercise, average respiratry rate befre and after exercise, and recvery time culd all be presented in ne table. In lab, yu will cllect data frm yur experiments in the frm f a list f numbers that may appear at first glance t have little meaning. Lk at yur data. Hw culd yu rganize the data set t make it easier t interpret? Cmputer-generated data tables can be created easily. Ntice that the table belw has a captin r title placed abve it that describes its cntents. Each title shuld als include the date and lcatin where the data was cllected. The title shuld give enugh infrmatin t allw the table t be understandable apart frm the text. each table's clumns need headings abve them (labels). Any units needed (inches, secnds, grams, etc.) shuld appear in the headings, nt within the table. Rws may als need labels, t identify each variable. High schl reprts wrking with specific animals r plants shuld include the scientific as well as the cmmn name. Always remember t underline r put int italics all scientific names. Several data tables may be included n ne page, as lng as the frmat is clear and easy t read. Tables are numbered cnsecutively thrughut a lab reprt r scientific paper. Table 1. Number f students at Lng Beach Plytechnic High since YEAR (A.D.) NUMBER OF STUDENTS (in thusands) M 3.3 Table 2. The number f brine shrimp fund in sectins f tubing after the shrimp were expsed t changes in light, ph, r temperature, n Octber 2, 1995 at Ply High. VARIABLES I SECTION 1 SECTION 2 SECTION 3 SECTION 4 CONTROL LIGHT 1 0 (light) (dark) ph 8 (acid++) 3 (acid-) 52 (base+) 3 (base ++) TEMP 13 (ht) 24 (warm) 38 (cl) 21 (cld)

13 EXAMPLES OF GRAPHS Graphs are a perfect way t visually present yur data. A data table will shw yur results in numbers but is ften uninteresting r difficult t interpret. A graph can take the same data, make eye-catching and easily shw large differences in yur results. Graphs are great t shw cmparisns between 2 r mre grups r relatinships amng the independent and dependent variable(s). The independent variable is usually graphed n the X (hrizntal) axis and the dependent variable is graphed n the Y (vertical) axis. By lking at a graph, then, yu can visualize the effect that the independent variable has n the dependent variable. A graph cannt stand alne - it MUST be preceded by a data table! The data table cntains the exact details frm an experiment that a graph ften cannt shw. They cmplement each ther: ne gives the details, ne displays the trends. The intervals labeled n each axis shuld be apprpriate fr the range f data s that mst f the area f the graph can be used. Fr example, if the highest data pint is 147, the highest value labeled n the axis might be 150. Generally, begin bth axes f the graph at zer (the extreme left crner). T avid generating graphs with wasted space, yu may signify unused graph space by tw vertical tic marks between the zer and yur lwest number n ne r bth axes. The intervals labeled n the graph shuld be evenly spaced. Fr example, if the values range frm 0 t 50, yu might label the axis at 0, 10, 20, 30, 40, and 50 Label each axis with the name f the variable and specify the units used t measure it (grams, cm, ml, etc). A key is needed if yu use different clrs r designs t visually separate data. A key is generally placed between the labels and the title, n the x axis (see example). The title fr a graph ges at the BOTTOM f the graph and like a data table, includes a brief descriptin f the kind f data the table cntains, the date and lcatin and any scientific names needed. Chse the type f graph that best presents yur data. Line graphs and bar graphs are mst frequently used. The chice f graph type depends 5 n the nature f the variable being graphed. Like data tables, graphs must be prperly labeled and titled Line graphs shw changes in the quantity f the chsen variable and emphasize the rise and fall f the values ver their range. Fr example, changes in the dependent variable pulse rate, measured ver time, wuld be depicted best in a line graph. Use a line graph t present cntinuus data Time (years) Ply High Lakewd Plt data as separate pints. Generally, d nt cnnect the pints dt t dt, but draw smth curves r straight lines t fit the values pltted fr any ne data set. If mre than ne set f data is presented n a graph, prvide a key t indicate which set is which.

14 Figure 1. Number f students attending Ply High and Lakewd High since Bar graphs are cnstructed like line graphs, except that a series f vertical bars are drawn dwn t the hrizntal axis. Bar graphs are ften used fr data that represent separate r discrete grups r categries, thus emphasizing the discrete differences between the grups. Fr example, a bar graph might be used t depict differences in pulse rate fr smkers and nnsmkers M Figure 2. Number f students attending Lng Beach Plytechnic High since Pie graphs are cnstructed in a circular manner, with lines crssing thrugh the center t create segments. Each segment fr data that represent discrete grups f data falling int percents. Fr example, a pie graph might be used t depict differences in eye clr in a grup f fruit flies. 8 CONTROL ph LIGHT TEMP 38 used

15 When yu set ut t write yur lab cnclusin, try t address these fur questins, in this basic rder: 1. What happened? (Remember, d nt g ver the measurements; talk abut the trends in the data) 2. Why did that happen? (This is where yu demnstrate yur science knwledge, bringing in the key vcabulary) 3. Hw d yu knw that happened? (This is where yu explain the techniques used t determine the results) 4. Des the data supprt my hypthesis? (An accept r reject rather than a right r wrng )