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UNIT 2‐ECOLOGY• Balance in ecosystems• Predation, symbiosis, and competition• Population size and carrying capacity• Invasive species• Food webs and energy pyramids• Biogeochemical cycles• Human impact on the environmentp• Ecological succession, climate change, and seasonal variation• Abiotic factors in aquatic ecosystems impacting life• Effect of resource use on the environment• Importance of biodiversity• Biomes

EQ:What is ecology? Ppp64‐65

Relationships or interactions and Interdependence

among living organisms

EQ:How are living organisms organized in the biosphere?

Starting from: atomsmolecules

cell parts cellstissuesorganssystems

organisms/individuals population

communityecosystemsbiosphere

ECOLOGICAL METHODS (pp 68)

ECOLOGICAL METHODS (pp 68)

There are 3 Types of ecological methods.

1. Observation & Questioning.

2. Experimentation‐Used to test a hypothesis‐ to have dependent and independent variables and p pcollect results.

3.Modeling‐Used to create a plan of the topic under study it because it is not possible to study it in the 

classroom.

What is the difference between a food chain and a food web? pp73‐75

What kind of relationships exist?

How are predators and prey populations related?

Food chain=1 link

Food Web=  food chains that are interconected/interacting

Chart Showing Predator –Prey Interactions

Types of relationships pp104

1.SYMBIOSIS*Mutualism ‐2+*Commensalism 1+ ø*Parasitism 1+ 1‐

2.COMPETITION

3. PREDATION

ECOLOGICAL PYRAMIDS pp77+78‐ ‐*There are 3 types   Pyramid of Energy; Pyramid of Mass; Pyramid of Numbers 

Answer the following EQ’sHow much Energy is transferred to the higher level?=10%, lowest energy is at top How much energy  is lost + in what form?  =90% lost as heatWhat types of energy are found in pyramid?‐Solar‐Chemical‐HeatWhy is the structure Pyramid‐shaped? Where are producers consumers & decomposers + what do they do?Each energy level =Trophic levelWhat is the role of decomposers? break down dead organisms‐ recycle nutrients

base

Chemical Energy

Factors affecting Populations of organisms   pp.132EQ: What are the ways population can be decreased?What are the ways populations can be increased?

Population increases

Population decreases

Emigration=

Immigration=Moving  in

Emigration=moving out

Death Rate

Birth Rate

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Limiting Factors in Population Growth pp 137

Carry Capacity Can be Limited byDensity dependent +Density independent factorsCompetition

Density dependent

PredationDensity dependentPredationDensity dependent

Parasitism + DiseaseDensity dependent Natural disaster + Weather

Density   ‐ independent

Chemical  Sprays, 

dependent

Chemical  Sprays, Density  ‐ independent or  dependent

GROWTH CURVES  ‐2 types

• Exponential –J shaped  pp133  Logistic‐S shaped pp134*Conditions‐No lack of resources , no predators     *Conditions‐Limited resources

No limit to growth  & no competition                *Organisms‐Most organisms

*Organims‐fast growing organisms like bacteria,                       

Slow growing org. like elephants, organisms

That are placed in a new Environment  .                                                become limited

CP is reached when resources become limited

Growth still occurs in Stg.1&Stg.2 but it is slower

Ecology Vocabulary  Words1.Biotic + abiotic pp.662.Producer + consumer  pp 69‐78         3.Autotrophs +heterotrophs pp.69‐70‐714.Herbivore+ carnivore +omnivore5.First level, Second level,Third Level consumer pp. 77 6.Food chain +food web pp.73‐746.Food chain  food web pp.73 74

7.Decomposers+detritivores+ scavenger pp.74

8.Phytoplankton + zooplankton  pp.75‐76

9. Trophic level + food pyramid pp 77

10.Photosynthesis + Chemosynthesis pp.70

BIOGEOCHEMICAL CYCLES‐ WATER CYCLE  pp81All BGC transform the nutrients and matter into other 

substances…the cycles  do not use up matter

EQ: What processes return water to the atmosphere?EQ: What processes increase water on the earth?

BIOGEOCHEMICAL CYCLES‐‐CARBON CYCLE   pp83EQ: What are the processes that recycles Carbon through the biosphere?

Know processes that add + remove C from atmosphere 

GLOBAL  WARMING‐CAUSE , EFFECT & MEASUREMENT    pp97 +177

Cause‐CO2 from Pollution. Effects: High Land and water Temperatures

Global Warming can be measured by measuring Land and Ocean temperaturesGLOBAL WARMING CAUSE

GLOBAL WARMING EFFECT

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CO2‐Increases  pp177Scientists are noticing that when CO2 increases, global temperatures are also increasing. Thus CO2 is believed to be the cause of global warming

BIOGEOCHEMICAL CYCLES

PHOSPHOROUS  CYCLE  pp84

BIOGEOCHEMICAL CYCLESNITROGEN CYCLE pp.86 Read

NUTRIENT LIMITATION /LIMITING NUTRIENT  pp86 Nutrients ‐chemicals needed by plants and animals like nitrogen + phosphorous + 

Potassium can be in short supply and limit productivity nutrient limitation

LAND‐On the Land‐Nitrogen, Phosphorous and Potassium are the limiting nutrients.p.86

WATER‐In fresh water‐Phosphorous is limiting

In Salt Water‐Nitrogen is limiting nutrient. 

ALGAE BLOOMIf Nitrogen is normally a limiting factor and there is a sudden  excess of Nitrogen‐in aquatic areas from runoff from nearby farmsFirst, algae begin to bloom…Then, they die, then decay. This uses the O2 in the water.O2  then becomes limitingArea becomes a dead zone as there is 

no O2 for aquatic plants & animals

ECOLOGICAL SUCCESSION pp106‐107Primary & Secondary Succession. These differ in terms of• Starting Point• Time involved in recovery• Biodiversity• Kind of activity that results

in primary  & secondary

• Pioneer species are the first species to inhabit the land in primary succession for example mosses, lichens, grasses

• Bare rock is just particles with no nutrients vs Soil with organic material

POLLUTION‐Acid Rain pp.164                                          Ozone Effect  pp165                   Cause‐CO2. NO2, SO2                                Cause‐CFC’sEffect: Erosion, Burning                             Effect‐ UV radiation‐cancer

CO2pp97

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Aquatic Ecosystems Can be Fresh water + Saltwater pp117

Freshwater‐*Rivers & streams 

*Wetlands‐lands under water, nutrient rich, they purify water by filtering nutrients. Ex.bogs, swamps, marshes

*Estuaries‐A wetland where river or fresh water meets salt water/sea. Photosynthesis is high, producers are abundant, sunlight is good, therefore they are nursery ground for aquatic life ex. Everglades mangroves.There is a lot f Bi 119of Biomass….pp119

* Phytoplanktons‐are producers in water +produce oxygen

* Ocean/Marine Ecosystems   pp120

• Different zones at different depths

• With depth‐sunlight and nutrients vary 

and therefore biotic factors change accordingly.

BIODIVERSITY pp 166‐172*BIODIVERSITY‐What is it and why is it important?Biodiversity can be Decreased by these        Threats• Altered Habitats• Hunting• Pollution• Introduction of New Exotic species…They new species have no 

predators when they are introduced, so they grow rapidly, this causes natural existing species to be crowded, destroyed or 

h f d i bi di i 168eaten therefore reducing biodiversity.pp168• Biodiversity can be Increased/Conserved by • Protecting Individual Species/Endangered Lists• Preserving Habitats and Ecosystems• Reforestation• Ecological Hotspots• Considering Local Interests.

VOCABULARY WORDS1.Biological Magnification pp161

This is the increase in concentration of a Toxic chemical , pollution that occurs in afood chain as a consequence of persistence(can't be broken down by anenvironmental processes)

2. Sustainable development pp157 Sustainable development (SD) is a pattern of growth where resources .are used to meet human needs while preserving or sustaining the environment. This allows us to meet the need not only in the present, but also for future generations.

3.Desertification 159Desertification is drying of landscaused by a variety of factors, such as climatechange, dryness & human activities,

desertification is a significant global environmental problem.

4.Ecological Footprint 173The ecological footprint is a measure of demand for

natural resources that may be compared with the land’s capacity to regenerate resources.

5.Ecological hot spot 171These are areas of the world where natural resources are threatened or b i ti t H t tbecoming extinct. Hotspotsare protected from Damage.6.Deforestation Removal of Trees

UNIT 2 VOCABULARY –Topics Ecology Slide # 8 also

2.1-Ecology, Interdependence, Biosphere, species, population, community, ecosystem, biodiversity, competition, parasitism, commensalism, mutualism, predation, invasive-species, biomass.

2.2-Biogeochemical-cycle, nutrient, limiting-nutrient, aquatic-biome, freshwater, marine, photic, aphotic , estuary, wetland, ecological-succession, primary-succession, secondary- succession, pioneer-species.

2.3-Growth-Curve, carrying-capacity, immigration, emigration, li i i f i l h l i i h li i i flimiting-factor, exponential-growth, logistic- growth, limiting-factor, density-dependent- limiting- factor, density- independent- limiting-factor.

2.4-Biological-magnification, climate –change, global-warming, greenhouse-effect, ozone-depletion, renewable-resource, nonrenewable-resource, conservation, sustainability

(approx.50words)

Learning Objectives‐Students will be able to…2‐1: Characterize ecosystems in terms of their biotic and abiotic factors. (SC.912.L.17.5)2‐2: Describe the interrelationships of organisms at various levels of biological organization. (SC.912.L.17.6)2‐3: Explain how interrelationships between organisms help maintain homeostasis within an ecosystem. (SC.912.L.17.6)2‐4: Compare the nature of interactions between organisms, including predation, competition, and symbiotic relationships. (SC.912.L.17.6)2‐5: Apply scientific knowledge and reasoning to form an argument about the importance of conserving biodiversity. (SC.912.L.17.8, SC.912.N.4.1)2‐6: Predict and analyze changes in an ecosystem resulting from the introduction of invasive species. (SC.912.L.17.8, SC.912.L.17.20) 2‐7: Describe the impact of pollution in aquatic ecosystems on human health. (SC.912.L.14.6) 2‐8: Describe the changes in communities over time, including changes in biomass, diversity, and complexity. (SC.912.L.17.4)2‐9: Use models to predict the effect of an ecological disturbance on communities within an ecosystem. (SC.912.L.17.4, SC.912.N.3.5)2‐10: Describe interconnections between biotic +abiotic factors, e.g. normal cyclic fluctuations and changes associated with climate change. (2‐11: Compare and contrast changes in communities resulting from long‐term changes and cyclical changes. (SC.912.L.17.4, SC.912.L.17.8)2‐12: Interpret data in charts and graphs. (SC.912.N.1.1) 2‐13: Predict changes in population due to changes in biotic and abiotic factors. (SC.912.L.17.5)2‐14: Justify explanations with evidence and reasoning. (SC.912.N.1.1)2 15: Distinguish between the roles of consumers producers and decomposers in an ecosystem (SC 912 L 17 9)2‐15: Distinguish between the roles of consumers, producers, and decomposers in an ecosystem. (SC.912.L.17.9)2‐16: Represent the relationships between consumers, producers, and decomposers in foodwebs. (SC.912.L.17.9)2‐17: Describe the pathway of energy through trophic levels and explain the reduction of available energy at each successive level.(SC.912.L.17.9)2‐18: Illustrate and analyze the biogeochemical cycles of water, carbon, and nitrogen through ecosystems. (SC.912.E.7.1, SC.912.L.17.10)2‐19: Explain the importance of biogeochemical cycles in the proper functioning of an ecosystem. (SC.912.L.17.10)2‐20: Predict changes in the environment resulting from human‐caused changes in biogeochemical cycles. (SC.912.E.7.1, SC.912.L.17.8, 

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ECO PRACTICE UNIT 2     pp1

1.The Algae at the beginning of a food chain isA. primary producers  B.primary consumers    C. herbivores   D.omnivores

2.How do most primary producers make their own food?    A.by using light energy to make carbohydrates                               B.by using chemical energy to make carbohydratesC.by changing water into carbon dioxide                                        D.by breaking down remains to make carbon dioxide

3.Which of the following organisms does NOT require sunlight to live?                                              A.chemosynthetic bacteria      B.Algae C.Trees D. Photosynthetic bacteria

4.What animals eat both producers and consumers?    A. Herbivores    B.Omnivores C.Chemotrophs D.Autotrophs

5.What is the term for each step in the transfer of energy and matter within a food web?A. energy path     B.food chain   C.trophic level   D.food pyramid

6.A bird stalks, kills, and eats an insect. Based on its behavior, which pair of ecological terms describes the bird?A. herbivore, decomposer    B.producer, heterotrophy        C.carnivore, consumer  D.  autotroph, herbivore

7.A model of the interconnected complex feeding interactions in a community from producers to decomposers is cA.food web    B.Population C.Ecosystem D.food chain

8.Only 10 percent of the energy stored in an organism can be passed on to the next trophic level. Of the remaining energy, some is used for the organism’s life processes, and the rest is

A.used in reproduction.    B.stored as body tissue.           C.stored as fat.     D.eliminated as heat.

ECO PRACTICE UNIT 2         pp29.No two species can occupy the same niche in the same habitat at the same time

A.because of the interactions that shape the ecosystem.     B.unless the species require different abiotic factors.

C.because of the competitive exclusion principle.                  D.unless the species require different biotic factors.

10. What is one difference between primary and secondary succession?

A.Primary succession is rapid and secondary succession is slow.

B.Secondary succession begins on soil and primary succession begins on newly exposed surfaces.

C.Primary succession modifies the environment and secondary succession does not.

DSecondary succession begins with lichens and primary succession begins with trees.

11.Which of the following is a factor that makes estuaries unique?

A. They contain a mixture of saltwater and freshwater. B. They are very deep and dark with a lot of producers.

C The are fo nd in mo ntain ranges and are formed b melting sno D The ha e a lot of biomassC. They are found in mountain ranges and are formed by melting snow. D. They have a lot of biomass.

12. Which of the following is true about nonrenewable resources?

A.They can be replaced through sustainable development.

B.There are plenty for people to use for a very long time.

C.Using them up will help keep the environment healthy.

D.They cannot be replaced after they are used up.

13.Burning of fossil fuels, deforestation, overgrazing and forest fires all contribute to

A. climate change. B.population. C.sustainability. D.transpiration.

14.A major factor that negatively affects biodiversity is

A.sustainable development. B.habitat loss. C.contour plowing. D.nonrenewable resources.

ECO Practice Unit 2 pp4

15.The benefit to a society using renewable resources is

A.renewable resources can be replaced. B.renewable resources cannot be replaced.

C.non-renewable resources take more space. D.non-renewable resources can be replaced.

16.If lake receives a large input of limiting nutrient, which of these would happen first?

A.an algal bloom occurs B.algae begin to die and decomposers take over

C.nitrogen compounds are recycled D.the concentration of oxygen drops below the necessary level

17.During primary succession in an ecosystem, which organismc are considered “pioneer species” for the ecosystem?

A.lichens and moss B.trees and shrubs C.ferns and grasses D.volcanoes and soil

18.Which are two ways a population can decrease in size?

A.immigration and emigration B.increased death rate and immigration

C.decreased birthrate and emigration D.emigration and increased birthrate

19.Suppose that a species of toads is introduced into a new environment in an attempt to reduce the population of insects. The toad has no natural predators in the new environment. The toad population would most likely

A. increase exponentially B.increase logistically C.decrease rapidly and dies out D.remain the same

20.Water lilies, an aquatic plant, do not grow in dry desert sand because water availability to these plants in a desert is

A.limiting factor B.the carrying capacity C.competition factor D.the logistic growth curve

21.What is the base of all ecological pyramids?

A.Consumers B.Producers C.Decomposers D.Detritivores

22. All of the following are threats to biodiversity EXCEPT

A. climate change B. building homes C. introduced species D. habitat protection

EOC PRACTICE UNIT 2 pp.6

23.What would likely happen if the number of grasshoppers suddenly decreased in the food chain shown: Grass--> grasshopper --> snake --> fox A. the snake population would decrease B. the fox population would increaseC. the snake population would increase D. the amount of grass would decrease

24.Water is returned to the earth’s atmosphere by which water cycle processes? A.evaporation and precipitation B.condensation and precipitation C.transpiration and precipitation D.transpiration and evaporation

25.An endangered species is most vulnerable to extinction when it has which of the following characteristics?A. high birthrate B.large variety in its diet C. small amount of competition D. small amount of genetic diversity

26.An invasive species of green algae has become established along the coasts of the Gulf of Mexico. Which of the following statements best explains why this species of algae has been so successful in the gulf of Mexico?

A. It is not a good competitor. B. It is not eaten by many animals.C. It reproduces slowly in warm waters. D. It requires more nutrients thanmost other algae.

27. Which substance is considered to be a factor affecting Earth’s ozone layer?A chlorofluorocarbons B ethyl alcohol C nitrogen gas D. Water vapor

28.In an ecosystem, which is the most likely reason for an increase in the producer population if there is an increase in the carnivore population?

A. Fewer Herbivores B.Higher temperatures C. Less food D. More oxygen

29.A researcher sprays a new pesticide on thousands of insects of the same species that live in a large field. A few of the insects survive. What can be concluded by the researcher?

A. The species of insects will likely become resistant to the pesticide.B. The ideal interval between the first and second applications of the pesticide should be increased.C.The pesticide has no effect on the species.D .The concentration of the pesticide was too weak.

30.Which sequence shows increasing ecological levels of organization?A .organism, population, community, ecosystem B. ecosystem, population, organism, communityC .community, ecosystem, population, organism D population, organism, ecosystem, community

EOC   PRACTICE   UNIT 7    pp.7

31.A plant species lives in an area with limited sunlight. Which physical adaptation would be most useful to the plant?

A. colorful flowers    B. large leaves     C. deep roots     D. waxy cuticle 

32. Which situation would result in the greatest increase in the human population?

A . decreased birth rate and increased death rate                   B.  increased infant mortality and decreased death rate

C.  decreased death rate and increased birth rate                    D. increased birth rate and increased infant mortality

33.In a forest ecosystem, which is an abiotic factor?

A.  the amount of rainfall      B. the size of the deer    C. the type of trees    D. the number of birds

34. Silt and nutrients from eroding farmland flow into a lake. As a result, which will most likely increase first?

A. fish population     B. shore vegetation    C. algae growth    D. dissolved oxygen

35.In the carbon cycle, atmospheric carbon dioxide is converted into organic material by which process?

A .cellular respiration      B.  Decomposition     C . Photosynthesis    D.  Transpiration

36.Recent climate data suggests global warming trend.. The most likely cause could be an increase in gas?

A. Oxygen     B. carbon dioxide    C. nitrogen     D.hydrogen sulfide

37. The branch of biology dealing with interactions among organisms and between organisms and their environment is 

A. economy.    B.modeling.    C. recycling.    D. ecology

38. All of the members of a particular species that live in one area are called a(an)

A. biome.   B. population.   C. community.    D. Ecosystem

EOC  PRACTICE UNIT 2      pp.9

39.What is the original source of almost all the energy in most ecosystems?A. Carbohydrates B. sunlight C. water D. Carbon

40. The movements of energy and nutrients through living systems are different becauseA. energy flows in one direction and nutrients recycle. B. B. energy is limited in the biosphere and nutrients are always available.C. nutrients flow in one direction and energy recycles. D. energy forms chemical compounds and nutrients are lost as heat

41. An organism that uses energy to produce its own food supply from inorganic compounds is called a(an)A. heterotroph. B. consumer. C. detritivore. D.autotroph

42.Organisms that obtain nutrients by breaking down dead and decaying plants and animals are calledA. decomposers. B. omnivores. C. autotrophs. D.producers

43. Carbon cycles through the biosphere in all of the following processes EXCEPTA. photosynthesis. B. transpiration. C. burning of fossil fuels. D.decomposition of plants and animals

44. The greenhouse effect isA. the result of an excess of carbon dioxide in the atmosphere.B. a natural phenomenon that maintains Earth’s temperature range.C. the result of the differences in the angle of the sun’s rays.D. an unnatural phenomenon that causes heat energy to be radiated back into the atmosphere

45. Which is a biotic factor that affects the size of a population in a specific ecosystem?A. average temperature of the ecosystem B. type of soil in the ecosystemC. number and kinds of predators in the ecosystem D. concentration of oxygen in the ecosystem

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EOC PRACTICE UNIT 2 pp 10

46.One of the main characteristics of a population is its

A. change over time. B. geographic distribution. C. dynamics. D. habitat

47. As resources in a population become less available, population growth

A. declines rapidly. B. increases slowly. C.reaches carrying capacity. D.enters a phase of exponential growth

48. If a population grows larger than the carrying capacity of the environment, the

A. death rate may rise. B. birthrate may rise. C.death rate must fall. D. birthrate must fall.

49. Which of the following descriptions about the organization of an ecosystem is correct?

A. Communities make up species, which make up populations.

B. Populations make up species, which make up communities.

C Species make up communities which make up populationsC. Species make up communities, which make up populations.

D. Species make up populations, which make up communities

50. In a logistic growth curve, exponential growth is the phase in which the population

A. reaches carrying capacity. B. grows quickly and few animals are dying. C. growth begins to slow down D.growth stops

51. A biotic or an abiotic resource in the environment that causes population size to decrease is a

A. carrying capacity. B. limiting nutrient. C. limiting factor. D. growth factor.

52. All of the following are limiting factors EXCEPT

A. immigration. B.competition. C. predation. D. human disturbances.

53. Each of the following is a density-dependent limiting factor EXCEPT

A. competition. B. predation. C. crowding. D. disease.

EOC PRACTICE UNIT 2  pp11

54. Which of the following is a density‐independent limiting factor?

A. earthquake   B.disease C. emigration    D. parasitism

55. The sequence of energy flow through a food chain is

A. primary consumers‐ producers‐ higher order consumers. 

B. producers‐ higher order consumers‐ primary consumers. 

C. higher order consumers‐ primary consumers‐ producers. 

D.producers‐ primary consumers‐ higher order consumers. 

E. primary consumers‐ higher order consumers‐ producers. 

56. In a terrestrial ecosystem, the trophic level that would contain the largest biomass would be the

A. producers.    B. primary consumers.    C. secondary consumers.   D. highest order consumers

57. In the past decade, which of the following has NOT been a major cause of the increase in the world's population? 

A.longer life span B. lower infant mortality  C. increase in birth rate  D.improved sanitation  E. preventative medicine

58.  A population's growth rate rapidly slows as 

A) changes in the environment take place.    B) the seasons change. C) evolution stops

D) new diseases cause their numbers to stabilize. E) the carrying capacity of their environment is approached..

59.According to this simplified water cycle, the process of transpiration is the process that A. causes photosynthesis in plants B. increases the rate of the water cycleC. releases water vapor from plants D. speeds the evaporation of water

60.New fuels are being produced by converting corn and grasses into compounds containing alcohols that can be broken down for energy in various engines. The purpose of this research is to

A. reduce the use of nonrenewable resources. B. increase the rate of air pollution.

C. reduce the rate of homeostasis in organisms. D. cause a loss of biodiversity in the rain forests

61.Which disease most likely occurs after excessive exposure to ultraviolet radiation? Pp163

A. malaria B.asthma C. skin cancer D. polio

62. The series of predictable changes that occurs in a community over time is called

A. population growth. B. ecological succession. C. climax community. D. climate change

63. What is one difference between primary and secondary succession?

A. Primary succession is slow and secondary succession is rapid.

B.Secondary succession begins on soil and primary succession begins on newly exposed surfaces.

C. Primary succession modifies the environment and secondary succession does not.

D. Secondary succession begins with lichens and primary succession begins with trees

64. The presence of wastes, such as plastic bags and motor oil, in lakes and streams miles away from developed areas suggests that

A. ecosystems are interconnected and human action can alter ecosystem equilibrium.

B. recycling programs have failed to conserve biotic resources.

C. natural processes can alter ecosystem stability.

D. direct harvesting practices have led to irreversible destruction of ecosystems

65.DDT and other pesticides used over 50 years ago are still affecting the environment today. Scientists have found these substances in recent glacier runoff. Glacier runoff occurs during the summer, when precipitation that has fallen on glaciers during the winter is released. Ice layers from existing glaciers have been analyzed. The results of this analysis show that the concentrations of DDT and other pesticides were highest about 10 years after the use of these substances was banned. This information shows that

A. DDT and other pesticides cause glacier runoff during the summer.

B. it takes humans over 50 years to analyze a glacier.

C. precipitation helps to break down pesticides.

D. the decision of one human generation may have an impact on future generations

The Interelationship /Correlation between Photosynthesis and Respiration

with water and Bromothymol Blue

with water and Bromothymol Blue + 

Elodea plant

with water and Bromothymol Blue 

+CO2

with water and Bromothymol Blue + 

Elodea plant afetr a few hours in darkness

         

Why does the Elodea plant turn  the Bromothyol Blue YellowWhich process is the plant carrying out?  

What will happen if a fish or another animal is added to Elodea and BB            What will happen if we place the plant in the sunlight again ?