B I 0 LOGY/A N S WE R S

Biology Answers

Part 1/New Discoveries Sea 3 Producer organisms: diatoms First-order consumers: copepods Activity 1/Putting "Goo" in its Place Second-order consumers sardines Decornposers.bacteria not illustrated! copepods and sardinesalso play a role in decomposingplant material 2,d 4. a. photosynthesis 3. a b. proteinsynthesistATP and DNA synthesis

4,b c. An increased in the water of both chemicals would occur. 5. d d. Eventuallya new balancewould occur after a 6. Larvaceans decrease in heterotrophs consumers!, e. A decrease in concentration would occur. 7. Scuba and glasslars! f. A bloom might cause pollution and deaths or an in- 8. Paradigm crease in heterotrophs. Eventually a new balance would be established. 9, Stinging tentacles 5. The guano industry would also suffer economic hardship. 10, Nannoplankton

For Further Study. Answers would depend on the article read.

12.a,b,d,i Activity 3/Life in Hydrothermal Vent Comrnunitiea 13.c,e,f,h 1. This is an open-ended question. Accept any sug- 14 g gestions that are factually correct. This should provide an opportunity for discussion of the conditions neces- 15.Scuba allowedus to see the abundance,diversity saryfor life. Tryto focuson the adaptiveability of and feeding methodsaf blue-waterplankton, organisms to this hostile environment.

16.They make the food web morecomplex, and they 2. Energysupply is the most limitingfactor. Since provide a link between nannoplankton and the rest of there is no light at these depths, the available energy shouldseverely limit the abundanceof living things. the organisms, etc. Instead,we find a well-developedbiological community. The key is the existenceof chemosyntheticorganisms Activity 2/Ocean Upweffinge at the base of the food web. 1. The biotic factorsof the upwellingecosystem are: Studentsmay also suggestthat a highertempera- ture than normal is found at this depth. This is true diatorns, copepods and sardines. But as one movesaway from the vent,the drops sharply. In addition, low do not 2. Abiotic factorsof the u pwellingecosystem are high seem to limit organisms in other locations on the deep and low systems in tropical Pacific, move- sea floor. rnent of surface water across the Pacific, coastal winds, nitrogen and phosphorus, and sunlight light!.

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3. Thespecifics of thefeeding relationships willbe gaseousoxygen Decompositionis the oxidizingof determinedbyfuture research. The following diagram organic matterback into simplercompounds. shows what is known: In photosynthesis,the energyis thatof sunlight tubeworms clams mussels trapped by chlorophylland reactedwith nutrientsto formorganic rnatter. In decomposition or !. chernosyntheticbactena the energy liberatedis in a chemicalform thatcarl ln addition,crabs and eelpout are scavengers, provideenergy for musclecontraction or otherenergy eatingalmost anything that is available. requinngbiochemical processes.

4. Themost noteworthy adaptation is theabundance 2. 106CQ!+ 16NOs + PO43 + 9 HpO+energy of hemoglobinin largetubewoms and clams. The C106H180046Ni6P+ 154 02 organisms'large size is possible because they con- a. to the nght centrateoxygen in hemoglobin-richtissues, Arctheradaptation isthe symbiotic relationship b. to the left developedby the tubeworms,dams and mussels with c. photosynthesis thechem~nthetic bacteria. The relationship appears to bemutualistic. The bacteria supply food to the three d. decomposition respiration! hostsand the hostsconcentrate the minerals the e. life processes bacteria need to live f. yes; heat and molecular bonds 5, lt wasthought that the absence of lightprecluded thedevelopment ofa large community. Chemosynthe- 3. would be lowerin somelower layers the ls hadnever been considered a basisfor the abun- 0>minimum. It is notlower in alldeep water because dance af large organisms. oxygen-nchwater from high latitudes supplies the cold waterthat occurs deep in the ocean. 6, Thisis also an open-ended question. However, some questionsthat are likelyto be listedare: How do 4. Nitrateand phosphateconcentrations would be theseoases of lifecome to becolonized? How stable lowerin thesurface layers since they react in arethese communities in viewof the limitednumber photosynthesisand are incorporatedinto organic of speciesadapted to thestressful conditions? Hydro- matter. thermalvents are not permanent features, so what is theimpact on the life history of the vent communities? 5. If onenutrient is exhausted,the processof Whatare the feeding relationships ofthe other mern- photosynthesiswill slowdown and stop. At this point, bersof the community? Are there practical applica- thecomposition of organic matter produced may have tionsof whathas been discovered about this unusual differentchemical ratios than the ratiopresented in ecosystem? thisexercise. This is broughtabout by having smaNer concentrationsof the nutrientin limitedsupply. Acthtty 4LMng BeteiaeaSana Gnitns 6. Physicalmixing between layers brings nutrients and Answers,observations, drawings and analysis will de- lighttogether to reactin photosynthesis. pend upon the organismsobservecl. Activity2/The Effects of Decayon Oa Part2/Biochemistry 1 The decompositionin jar 1 usedO~. Actfvtty1/Photosynthesis andDecornpositton 2. Temperaturechanges might cause differences, 1.Nutnents CO~, NO3, PO<'!+ water water holds less Oq. organic matter + oxygen 3. Thedecomposition in jar 1 usedup O~. Photosyrilhessoccurs when chemicals containing carbon,nitiogen and phosphoruscombine with the Actfvfty3/E~ of Plantson 0, hydrogenand oxygen inwater and with the energy from sunlighlto producesdid organicmatter and 1.There is moreOz in Var1 becauseof photosynthesis 8/88 BIOLOGY/ANSWERS

2 Temperaturechanges might causedifferences, Part 3/Animal Adaptations water holds less Oz, Activity t/Planktan, Nekton and 8enthoa Their 3 Photosynthesiscaused the difference.

Activity 4/Temperatureand O~ 1. d

1 As the water is heated, the amount of Oz decreases, 2. c

2 When algae bloom, the onesthat are lower die due 3. a to lack of light. Thusthere is decompositionwhich releases heat. Water holds less O~, and fewer fish can 4. c live, 5. d Actfvtty 5/Determining Pigments in INarine Algae Using PaperChrornafooraphy 6. drag !

1 The answersto this depend on algae used and 7. boundary layer results 8. low 2 Spinach will havebolder colors more pigment!and will be similarto greenalgae Ulva!. 9. drag

3 Chlorophylland other pigmentsare soluble in 10. Surface area-5cm x 6 sides = 150cm~ acetone but not in water. Volume - 5cm x 5cm x Scm = 125cm~ 4 The darkerthe color on the chrornatograrn,the 150 =6 greater the concentration of pigment will be However, 125 =5 this is a very qualitative observation Thereis only one unit of surfacearea for every5 5. Greens and to a lesser extent yellow, blue and unitsof volume.This is not enough surfaceto feed the orange are least useful in providing energy since plankton these are the colors that are being reflected. The other light waves are being used for energy. 11. Anemone A lives in a high turbulent area, such as a surge channel. The short, fat shape reduces the 6 Other pigments are not soluble in acetone or amount of surface exposecl to drag and therefore petroleum ether. stress. Anemone B lives in a quiet, stable environ- ment The tall, thin shape shows that this anemone 7 The pigmentsmight dissolveright into the . doesn't experience a great deal of stress.

8. The auxiliarypigments function to transferenergy to 12. At a low Reynold's number, water is thick like but- chlorophyll; this aIows the utilization of more of the terscotch. Consequently, copepod arms act more like light energy. scoops than filters. They push parcels of water to their mouths. This makes them an even bigger part of the oceanic food chain.

Activity 2/What Shapes Mean Speed

Answers will vary.

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Part 4/GeologicHistory and the 10. As competition for space and food increased and Oceans the numberof organismsincreased, those with spe- cial adaptations that suited them for new environments Activity 1/Personal Timeline had a survivaladvantage. This processcontinues as vacant niches are filled. Check individual time/ines. 11. Ocean life contributed to an increase in the con- Activity2/A Classroom Geologic Timeline centrationof the layerthus providingprotection from radiationand making it possiblefor terrestrialIiie 1. The benefitof radiometricdating is that it is to safely evolve. reasonablyaccurate. The disadvantageis that not all rock has a radioactivesample with a half-lifethat is in 12. The theory of plate tectonicsproposes that the a usefulrange. Some rocks don't haveany radioactive continents are riding "plates" that cover the earth like isotopes a skin. New materialis added Io a plateat the ocean ridgeend and destroyed at the trenchend, resulting 2. Marine invertebrate fossils are the most abundant. in constant movemenI. 3. We find humans in the Cenozoic era and the 13,The word "evolution"means change over time. Quaternaryperiod. 14.As the continentsmove, the shape of the ocean 4. Glasssponges, sharks and horseshoecrabs are ex- basinscan change. If the shape of the basinchanges, amplesof very ancientorganisms that arestill alive then the water level will change. today. 15.If oceansbecome deeper, organisms that depend 5. Possible explanations for mass extinctions include on shallowseas will becomeextinct. They are rot changesin the shape and geographicaldistribution of adaptedto the deeper oceans.Shallow waters are oceans, meteorites and comets. warmer with more uniform water movements. If these 6. TheEarth was in existencefor about2 billionyears factorschange, then organismsadapted to them will die. beforethe firstlife appeared. 7.Blue-green algae appeared about 2.7 billion years 16. Extinctiontoday might be occurringdue to thermal ago,marine algae about 600 million years ago and or chemicalpollution, loss of the ozone layer,loss of the firstland plants about 475 million years ago. territorysuch as rain forests,overhunting or over- harvesting, etc. 8. Lifewas in theoceans about 2 billionyears before life appeared on land. 17.Organisms change over time because they are reacting to changes in the environment, Natural varia 9, Sincelife is so dependent on water, beginning in tions are selectedby changingenvironments the oceansmeant that no specialadaptations were necessaryfor obtainingand preserving water. Repro- 18. B is the oldest rock because more of the LI-236 ductionwas simple in the wateryenvironment, and has decayed, maintainingshape was simple in the buoyantwaters. Thefirst cell was bathed in waterand the necessary Activity3/Fossli Lab chemicalsfor life.It did not riskdrying out. Answersvary depending on choice of lab fossils.

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Part 5/Seashells and Scientific haveone shell, a radulaand a well-developedhead Names and eyes.

Activity 1/Designing a DichotomousKey 12.Snails crawl on the surfaceof rocksand scrape algae with their radula. Clams burrow into sand or Answerswill vary accordingto shellsused. mud and filter food from the waterby pumping it through their siphons and gills. Activity 2/Usings DichotomousKey 13. A chambered nautilus is a cephalopod, not a 1. a!G gastropod. It has no radula and uses arms and ten- b! G tacles to capture food. The shell is filled with hollow c! B chambers. Snails have none of these characteristics. d! B e! C 14. Scientific names are always in Latin, do not f! PC change from place to place, are based on the Lin- g! PG,B,C naeus system of classification, are made from the h! B genus and species name. and are aJwaysunderlined. i! C Common names are in any language, can be different i! PB from place to place, are based on local culture and k! G are not underlined or capitalized. I! B rn! B 15.Clams filter seawaterto eat plankton. n! C o! P 16. Chitons are found stuck to rocks in the sea.

2 Answers wil! vary with student. Possibilities include 17,The seven divisions are: kingdom, phylum, class, alphabetically, by type, etc. order, family, genus and species.

3. The system is called the Linnaeus system of 'l8. Humans use mollusks for money, Jewelry,food, classification. buttons, decorations and pearls.

4. Taxonomists 19. Answer varies by student.

5. It is a key used to identify organisms It has at least 20. Their food doesn'I move so that they don't have to two choices at every step. be quick to catch it. They can pull their bodies all the way into their shell for protection. 6. The common features are. soft bodied, muscular foot or arms, visceral mass, mantle, shell, gills, 21. Organization of living things is important so that trochophore larva. people can communicate intelligently about them. The organization helps explain relationships and evolution 7. The four malor classes of mollusks are: polypaco- of the organisms. In addition, a good system makes phora, gastropoda, pelecypoda, cephalopoda. identification much easier.

8. It is in the class gastropoda. This class has a radula, Part 618ehavior of Ocean Cmattjres one-coiled shell, head and eyes, and an asymrnetncal visceral mass. Activity 1/Biologicsl Clocks

9. It is in the class cephalopoda, which means 'head- 1. Green crabs are most active during a combination foot." Yes, it is internal. of high and darkness.

10. Chitons Yes, they have eight internal shell plates. 2. Solar rhythm is the most important factor.

11, Pelecypoda. Bivalves have two shells, no radula, 3. Green crabs are darkest at noon. no head, primitive eyes and two siphons. Univalves 4. Solarrhythm is the most importantfactor. B /91 BIOLOGY/ANSWERS

S.The green crabs' behavior isinternally/genetically Activity4/The Sea Worm controlled. 1. Themaximum gain was 60 percentabove 6. Solarrhythms control the migration ofthe diatom, its initialweight. Hanfzschia. 2. The weightgain is due to the diffusionof waterinto 7.Staying below the surface keeps Hanfzschia from the worm. This occurs becausethe concentrationof beingcarried away by waves, water is lessinside the worm than it is outside Accord- ingto the principlesof ,rnolecules wilf tend to 8.Coming to thesurface at noonallows the organism move from an area of greaterconcentration to an area to takeadvantage of lightfor photosynthesis.. of lesser concentration.

9. Again,the behavior of Hantzschiaisinternally/ 3.The weight loss can be explained by active transport geneticallycontrolled. The worm begins to excretethe water that entered during the first five to six hours, 10.During high tide, fiddler crabs are quiet in their burrows;during low tide, fiddler crabs emerge to look 4. This is an exampleof homeostasis.After a time, the for food. wormbegins to restorethe balanceof saltin its body fluids. It is interestingthat it does not seek to maintain 11.In conditions of constantlight and temperature, the this balanceimmediately. rhythmperiods lengthen and no longercorrespond lo the tidal rhythms. 5. An organismthat livesin coastalregions is sub- jectedto frequent changes in salinitydue to runoff 12.Immersing thecrabs in orlowering their from the land and the effectsof the .Active trans- temperaturecan restoretheir environmental clock. port requiresthe expenditureof energy.The sea worm hasdeveloped an intriguingphysiological adaptation. 13.Hiding during high tide allows the fiddler crab to Ratherthan expending energy for a temporary avoid predators. changein salinity,it simplytolerates a periodof irn- balancein its internalbody fluids. H~r, if the Activity2/The Fkkfler Crab Experiment higherenvironmental salinity persists, then it beginsto lowerthe water content of its fluidsby excretion.This Answersdepend on students. is usefuland efficient for an organism that is subjected to frequentchanges in environmentalsalinity. Activity3/Salinity Changee ancf See Animals 6. Tosurvive in coastalwaters an organismmust 1.The body fluids in organism C remain unchanged evolvemechanisms fortolerating or adjustingto fre- asthe external salinity changes, Since salt tenets to dif- quentchanges in salinity.Most marine organisms fuseinto organism C whenthe salinity of the environ- havenot developed this ability. Therefore, they cannot mentgoes above PY0, the organism must do oneof inhabitcoastal regions The salinity of theopen ocean thetwo things: prevent the salt from entering orex- is fairlyconstant. Consequently, the abilityto cope wiN cretesalt at a rateto maintain a constantinternal changesis not foundin mostmarine organisms. concentration. 7.The cells must tolerate the changes in salinity.One 2. OrganismsA and B havean increase in internal wayto do thisis by activelytransporting the diffusing salinityas the salinity of the environment increases. salt molecules outward. OrganismA eventuallyreaches a point where its inter- nalbody fluids are in balance with the external salinity. 8, Withthe development of specializedtissues and OrganismB always maintains aninternal salinity less organs,more highly evolvedorganisms can regulate than the environment. processesthat simplerorganisms do not.

3. It isdifficult to saywhich situation ismore efficient or 9. Organismssuch as salmonand eels are migratory adaptable.The important thing is the organism survives, fish.To cope with the changein salinityfrom a Whetheritdoes so by tolerating higher external salini- freshwaterriver or laketo theopen ocean, these tiesor by alteringits internal salinity is notcrucial. Both organismsmust tolerateinternal changes or counter wayssolve the problemof a changingenvironment. the changeswith regulatoryprocesses. B/92 BIOLOGY/ANSWERS

Activity 5/Homeostasison a Graph Part 7JMan Under the Ocean' s Surface Figure 8 Changesin salinity Activity1/Understanding Diving Physiology

40 1. A diver feels the effects of increasing pressure in y Organism A 35 the lungs, sinuses and ears. ~ 30 ~ Organism B ~o 25 2. Increasingpressure external!reduces the sizeof the lung air spaces. o 20 o Organism C >5 i to 3. The air in the lungs expands. 05 4. Diverscan get nitrogennarcosis at great depths because the of nitrogen is greater at 1 0 2.0 3.0 4.0 higher and therefore enters the tissue fluid it4iexternal salinity in greater amounts.

Activity 6fThe HomeostaticRelationship Between 5, The symptomsof nitrogennarcosis are similarto Water Temperatureand RespirationRate in intoxication acting silly,irrational and in an unsafe Marine Fish manner.

1. Generally,the higherthe temperature,the fasterthe 6, A hangover, fatigue alcohol. excess carbon dioxide, respiration rate. inexperience and anxiety can lower a diver' s resistance to 2. It varies. 7. Ascendingquickly from great depths can causethe 3. It varies. bends;too many of the gases in the tissuesand blood come out of solutionand form gas bubbles that get in 4. Thermal pollution is likely to increase the rate of the loints and cause pain. respiration in fish. 8. Recompressionin a hyperbaricchamber with 5. Otherfactors that might affect respirationrate are: subsequent slow can be used to treat activity level of fish, depth of water, health, light and the bends. amount of oxygen dissolved in the water. 9. Obesity,sleep loss,certain drugs, hypercoagulability, 6, Breathingis increasing the passng of waterover high altitudediving and work rate at the specificdepth the gills!,this suggeststhat the metabolicrate may be can reduce the validityof the No-Decompression increasing due to increased intake of oxygen. How- Limits Table. ever, it is possible that the fish is simply increasing because the oxygen level in the water is Activity 2/Tha Hamoaponge decreasing. 1. The Bonaventurasare able to removeoxygen from 7. Answers may vary. seawater with the hemosponge, which is a mixture of polyurethaneplastic and hemoglobin.The hemo- 8. The student should answer that the fish respiration globin maintainsits abihtyto pick up oxygenand is rate increased to maintain a constant oxygen supply able to remove oxygen from seawater. to the tissues. 2. The hernospongecould modify 9. The fish has to adapt breathe fa5er! when the and the method used to supply air for submarines water temperature increases to maintain a stable inter- and subrnersibles. nal environment i.e. a constant level of oxygen!.

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3. Yes.It is believedthat a tankthat will filter seawater Activity5/The Hf/drolabUnderwater andremove oxygen will replace the compressed air ResearchFacfilty systemused in . 1. Dunngsaturation diving, a diveris exposedto an 4. It willallow divers to divefor longer periods of time inertgas at a fixedhigh pressure long enough for all withoutfear of runningout of air. the bodytissues to absorball the gasthey can. No additional gas can be dissolved in the tissues 5. Hemoglobinabsorbs the oxygen. It is known for its abilityta bindoxygen at the interfacebetween the 2. He maydevelop the bends.An incompletedecom- organismand his environment, either at the air-lung pressionwill leave nitrogenbubbles in 's interfaceor the water-gillinterface tissuesat a higherlevel than the partialpressure at the surface.When he ascends,if it is notslaw enoUgh, he Activity3/Heffurn Ohrfng risksdeveloping the bends.

1. Helium 3. Time and depth

2. Four and a half times

3. Commercialdivers use the helium system the most. It allowsthem to diveat greater depths without developingnitrogen narcosis.

4. It allawsgreater diving depths

5. False

Activity4/8ubmersiblea

1, Depth and time

2. Theinternal pressure of thesubmersible remains equalto surfacepressure so there will be noproblem with nitrogennarcosis or the bends.

3. The Trieste I

4. Diversin submersiblesare at surfacepressures. Thissystem offers the ability to dive to thebottom of theocean floor without developing the bends or nitrogen narcosis.