ACT Past Papers with Answers

Based on FicFure 2, of the onion root tip cells that were in ]nitosis, the proportion that were IL prophase is clos- est to which of the folLowing. Cell I Cell3 100 305 500. 305 305 loo 30) 500 Cell2 Cell4 Figure 3 Figure 3 adapted from Pet¢r H. Raven, Ray F. Evert. and Susan E. Eichhorn, 5iology ol Plants, 4th od. (D1986 by Worth Publishars, nc.

During the gel elcctrophoresis, the DNA fragments moved toward the electrode shown al the bottom of Figure l. Therefore, the chaige of the DNA fragments must have been.. .4. positive, btcause opposite charges attract. negative, becaiise opposite charges attract. negative, because like charges attract.

B

Based on the results of Tria]s 3-5, IE an additional trial is performed with M:= 0.060 kg and r - 0.100 Iii. KE ai Point U will most likely be: H, between 0.020 J and 0.025 J. The cart's gravitation.al potential energy, PE, at Points S and U and the cart's kinetic energv, KE, at Point U are shown ID Table l. When the.cart was on the floor, PE was zero. The cart's total mech2nical'energy, TME, at a given point equaled PE + KE at that point. TME at Point S itiillus TME at a second point equaled the amount of. TME conveited to heat by friction between Point S and the second point.

The rcsults of Trials 1-3 indicate that as the radius of the loop increased, the ]ninimum height of Point S required for the cart to roll completely through the loop: increased only. remained constant. varied, but with no general trend.

B

Which of . the following ranks Points S, T, and U in oider. from'the point'at which the speed of the cart was 'slowest to the point at which the speed of the cart Iwas fastest during any given trial? G_ Point S, Point U, Point T Figur8 1 and Table 1 adapted from T. M. Cooney, D. F. McGrail, and R. D. Unruh, eds, Physics Resources 2nd Instructional Strat8- gies for Motivating Students. @1993 by The College of-Nalural Sci- ences, The Universily of Northern IDw2. AGT-66C 42 GO ON TO THE NEXT PAGE. 40000000004 Passage IV Alcohols are caibon Co￿pOUndS that contain a hydroxyl (-OH) group bonded to a C atom. If the hydroxyl- bonded C atom is bonded to only one other C atom, or Lo no other C atoms, the alcohol is a primary alcohol. Table I lists the. chemic.al formula, melting point, and boiling point for geveral primary alcohols. l-propanol

Accoidiiig to Figure 2, as the percent H O by mass in an ethanol/H O solution incIeases froin Ogo to IOOIYO, the viscosity: increases only. illcreases, then decreases. l-piopznol

The prirnary alcohol l-hexanol has the che]lli¢al for- mula CH3(CH ),OH. Based on Table I, the boiling point of l-hexanol is most likely: less than 115°C. betvieen 115°.¢ and 145°.C. gr.eatcr :han l.

W,liicli' of ":the 'alcohols listed in Table I bas the lowest freeziJig point.?: Ethanol B q l-propanol methanol -20-10 0 10 20 30 40 50 60 70 temperature (°C), Figure I . 201 According to':.Figure 2, at 20°C, the visco£ity of a methanollH,O. solution that is Iolo methanol by mass is..,.close'st*to :the,yiscosity of which of the followintr u]ethanollH O sollltions? J, 90Yo methanol by mass

J

The Fesults of Experiment 2,are best reprcsented by which of the followillg .cryaphs?

Which of the followillg statements best explains the results of Experiment 3 ? The magnetic force exerted on the borseshi)e magnet by the magneEic field of Seg- ment AB: increased as the length of Segment AB was increased. increased. increased as the current flowing through the circuit.. was increased. cuit,was increased.

Based On the results of Experiments l and 3, it" can Jnobl reasonaDly be inf¢ii"cJ tha( iri LAperimeni i thc length of Segment AB was: 'G. between 2.0 cm and.3.0 cm. ACT4eic 45 GO ON TO THE NEXT PAGE. 40000000004 Passage Vl Key aLI￿oSphe￿C CO2 concentraLion global tempeTatuie deviation CO2 IS Pilt into Earth's atmospbere by human aciivi- ties and by llatural processes such as diffusion from the oceans. AtmosphcTiC CO2 affects Earth's cliEnate. In general, as the atn]ospheric CO2 concentration increases, more infrared radiation from Earth's surface is absorbed by CO and the average global temperature rises. The atmospheric CO2 concentiation that existed at any given time over the past 160,000 years can bc determined from air tiappe(l in bubbles in Antarctic ice foimed at that timc. Figure I shows the aimospberic CO2 concentration over the past 1,000 ye￿s. to 360pprn, 300 260 240 2200 360 340 340 320. widesprea<i burning of fossil fuels begins :. 320 160 300 160 140 120 100 80 60 40 20 0 thousands of years ago 300 280 280 Figure 2 1000 1200 1400 year 1600 1800 2000 Figure 2 adapted from Stephen Schneider, "The Changirig Cli- mate. Q1989 by Sciènlili.c Ameri¢an. .Two scientists discllss why the average global. temper- ature has risen over the past l io years. Figure I Figure 1 adapted frorll International Panel on Climate Change., 'Cli- male Cnange 2001= The bc4en.ific Basis." ¢)2001 by Cambridge Univeisity Press. Scientisf I Global warming is a direct result ot the CO2 Put into the air by the widespread burning of fossil fuels. Figuie I shows that. for hundreds of years prior to 1850, the atIiio- spheiic 'CO2 concentratloll was relatively constallt at around 280 parts per million (ppm). Since 1850, a Steady increase in the amount of fossil fuels burned has cau8ed the atmospheric CO2 concentration to incrèase, reachiiig

In Experin]ents I, and 2, the direction in which the cur- reni flowed through the'circuit determined which of the following. A, Length of Segment AB hoiSc8hoe ttiaJnet ' magnet by th& magnetic field of Segment AB

Suppose the curIent had flowed in the same direction in Experiment 3 as in Experiment 2. Based. on the results.of Experiments l and 2, with the Length of Seg- ment AB équal to 2.0 cm, thc scake reading most Likely would have beetl..

Suppose Scientist 2 asserted that theie have been times over the.past 160.000 yeaTs at. which the avera(ye global temperature has "been higher than .it is today. To support this assertion, Scientist 2 would rnost likely cite. the temperature data in Figure 2 for which of the following times? 85,000 years ago

Given Fi.trure I, Scientist I would most likely claim that from tkne year 1000 to the Ye￿ 1600, the averaoe global ietnperature". increased .by More than 2°C. .changed by les£ than.2°C, if at 211.

Assllme that the present-day average global tempera- tUTe is 22°C. Given Figure 2, the two scientists would most likely claim thai the average global ternperature 140,000 years ago was closest to which of ttLe followino? ACTQéG 47 . GO ON TO THE NEXT PAGE. Passage Vll

How, if at alj, would the results have been different if a dialysis bag with pores large enough to allow H O, I and starch molecules to pass through had bccri used in Experiment 2 9 ' A. The dialygis bdg would b2ve swollen and burst. B: A reddish-brown color would have appeared in both the dialysis bag and the beaker. ysis bag and the beaker. The net movement of H O molecule8 across a semi- permeable membrane Irom a region of higher H O conceD- ' tsation to a region of lower H O.. concentration is called Osmosis. A semipErmeable nieMbranE, such as dialysis tubing, is a barrier with tl.Jly PQTes that allow only mole- cules under a certain size, such as H O ￿Olecules, to pass. through. Other srnall molecules can a180 tnigrate from higher concentr.ation legions to lower concentration regions. A dilute starch solution and a dilute iodiiie (12) solu- tion were each prepared in H O. The 12 sollltion had a ' higher concentration of dissolved particles than did the staich solutiou. Therefore, the starch solution had a higher concentration of H O than did Lhe 12 solution. Molecules of 12 are larLYeT tban H O molecuIes, but are much smaller tlian starch molecules. A'starch solution is milky-white. An I solution is ieddish-brown. Mixillg. starch and 12 solutions 'ilI resuLt in a bluc solution..

In Experiments l and 2, Mihat did the beaker contain before submersion of the dialysis bag. Experifflent I Experiment 2 starch solution 12 solution starch Solution starch solution distillecl water distilled water

In Experiment I, before Lhe dialysis bag ivas placed in the beaker, the solution in the bag .was: -4, blue. rnilky-iwhite, reddish-brow'n. -colorlegs. Experiment I A, sealed bag made of dialysis tubing (a dialysis bag) containing the 12 solution was submerged in 2 beaker con- tainÉng the starch solution. Aftei I hr, the bag had swollen fron] its original size. The solution arot2nd the outside of the bag was blue, but no blue coloratioll was evident within the bag.

Sugar molecules do llot p.a%s thtough the dial)TSiS bags. used in Experiments 1-3 and &re coloTless when dis-._ solved in H O. If Experiment 3 were repeated. .but the bag was instead filled with a sugar solution, the bag would: swell, and the solutions both inside and olltside the bag would be colorIéss, shrink, and the solutions both inside and outside the bag would be colorless. swell, and the solutions both insidè and outside the bag would be reddish-brown. shrink, and the solution inside the bag would be reddish-brown while the solution outside the bag wou]d be coloiless. Expériment 3 A dial.ysis bag containing the 12 solution was sub- merged in a beaker containing. distilled H O. After I hr, the bag was swollen, and the solutions both inside the bag and outside the bag were reddish-brown. ACT-66C 48 GO ON TO THE NEXT PAGE. 40000000004

,In ExpeTirnents l and 2,.s.tarch molecules were able to move: only into the dialysis bag. ncithcr into nor out of the dialy.sis bag. END OFTEST4 STOPI DO NOT RETURN TO ANY OTHER TEST. ACT-66C 49 OPENACT provides you the answers for ACT Form 66C: English