Plant and Animal Responses to the Environment

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Biology 3.3 Responses to the Environment

Biology 3.3 Responses to the Environment

AS 91603 5 External Credits

Ms Gibellini 2014

Achievement StandardDemonstrate understanding involves describing plant and animal responses to their external environment. The description includes:the process(es) within each response and/or the adaptive advantage provided for the organism in relation to its ecological niche.Demonstrate in-depth understanding involves using biological ideas to explain:how the responses occurwhy the responses provide an adaptive advantage for the organism in relation to its ecological niche.Responses are selected from those relating to:orientation in space (tropisms, nastic responses, taxes, kineses, homing, migration)orientation in time (annual, daily, lunar, tidal rhythms)interspecific relationships (competition for resources, mutualism, exploitation including herbivory, predation, and parasitism)intraspecific relationships (competition for resources, territoriality, hierarchical behaviour, cooperative interactions, reproductive behaviours).External environment will include both biotic and abiotic factors.

Exam SpecificationsCandidates should be familiar with graphical and tabulated data.

Candidates should be familiar with the following terms:agonistic behavior endogenous home rangeauxin entrainment kin selectionbiological clock exogenous photoperiodismcooperative breeding free running period zeitgeber.courtshipTopic OutlineThe Basics abiotic, biotic, ecological niche

How/Why Respond

Responses in space

Responses in time

Interspecfic relationships

Intra specific relations

The BasicsAbiotic non livingTemperatureLight intensityMoistureSubstrateChemicals/pH

BioticPredatorsPreyCourtship and mating behaviours

Online Activities1. Watch the following clips, complete the quizzes.

2. Read through the following page

3. Complete the following activity to test your understanding BasicsEcological nicheWhere an organism lives, what it eats, what eats it, when it is active, adaptations it has to survive

Realised nicheWhere the organism is actually found due to limiting factors competition, lack of resourcesFundamental nicheWhere the organism could potentially be found

Why Respond?Why respond? - put your ideas onto the following padlet brainstorm

Adaptive Advantage - directly or indirectly helps individual's survive orreproduce

What is the adaptive advantage of being able to respond to the environment?

Get maximum sunlight for photosynthesisGrow roots towards nutrients and water sourceMove to warmer surroundingsHide when its daylight or too cold conserve energyOnline Activities1. Watch the following clip, read the information and answer the quiz

Stimulus:Anything that causes an organism to react. CauseStimulus : singularStimuli: plural

Response:Any change an organism makes as a result of a change in the environmentEffect

The Basics

StimulusPhoto light

Geo/gravi gravity

Hydro water

Chemo chemicals

Thigmo touch

Helio sunlight

Thermo temperature

How do organism detect changeAnimals use their sensesSightHearingTasteTouchSmell

Plants use chemicals and hormones to detect changes in their environment

How do animals respond?InnateBorn with behaviourSpiders spinning a web

LearnedTaught behaviour over timeChimps using stick to get ants from a log

VideosInnate BehaviourLearnt Behaviour

Learnt and Innate Human BehavioursAim:To unlearn an innate behaviour

Method:Blow across the eye of your partnerWhat happens? Did the person do this consciously? What is the adaptive advantage of this behaviour?Repeat (blowing across eye) at 10 sec intervals, record how many times you do it before the person learns not to react What is the stimulus? What is the response? What is the adaptive advantage of unlearning this innate behaviour?

Online Activities1. Watch the following clips

2. Read the following information TypesWhat are the differences between innate and learned behaviour?

2. What is the adaptive advantage of:

- having innate behaviours?

- being able to learn behaviour?



Growth movements slowchange in size/shape of cellsControlled by hormones

Turgor movementsFaster, reversible Water content of cells changesHow do Plants Respond?Plants use a range of hormones to respond to stimuli:

Google doc of tables

HormoneWhere is it madeEffect siteActionEffectAuxinGibberelinCytokininsAbscisic acid (ABA)EthylenePlants use a range of hormones to respond to stimuli:

HormoneWhereEffect siteActionEffectAuxinShoot tip (meristem)Growing regionsCell elongation due to turgor pressureTip bends towards stimulusGibberelinFruits, seeds, growing buds & stemsWhole plantGrowth of cells

Breaking of dormancyGrowth, germination of seeds, flowering, fruit growthCytokininsRoots & fruitBranch & leaf budsPromotes cell division and differentiationGrowth of lateral branchesAbscisic acid (ABA)ChloroplastsWhere fruit & leaves join to plant. SeedInhibits growthCauses fruit & leaves to fall from treeCloses stomataPromotes seed dormancy

EthyleneRipening fruitCellular metabolismIncreases sugar in fruitRipens fruit & leaves and causes it to fall

Online Activities1. Watch the following video, read the text, complete the quiz

Plant ResponsesVernalisationflowering or germination after a cold snapEnsures flowering/germination in spring

DormancyArrested (slowed) plant growthEnsures survival during winter/summer drought

AbscissionLeaf fallPrevents leaves freezing in winter

Jellybeans and AuxinAim: To demonstrate effects of auxin in the shoot.

Method:Create a shoot with small jellybeans (5 on each side) and half a marshmallow at the top (apical meristem) take a photo

2. When exposed to light lollie pop, IAA (choc chips) is released from the marshmallow (apical meristem) and travels to the dark side of the stem take a photo

3. The IAA (choc chips) is absorbed into the cells on the dark side, causing these cells to enlargeslowly remove the choc chips and replace 3 small jelly beans with large ones on the side opposite to sun one at a time, ensuring the top and bottoms of jellybeans are always touching and the middle, take a photo each time

4. Keep the jellybeans ALL touching and the top two jellybeans ending at the same point with the marshmallow on the top.

Results:5. What happens to the direction of growth? Why?

IAAThere are many types of AuxinsIndole Acetic Acid is involved with cell elongation

AuxinAuxin is a plant hormone which causes cells to elongate

Auxin is made in the tip, and moves down the dark side of the shoot, causing the shoot to bend towards the stimulus

Auxin is soluble in water, but not mica or glass

Auxin also moves with gravity to lower side causing elongation and shoots to grow up out of soil

Stem CuttingsAim: Investigate the effect of rooting hormone on the rate of root development.

Method: (tissue culturing) see worksheet

Sterilize utensils, workspace, containers(the trick is to keep things as sterile as possible so that you grow plant tissue and not bacteria or fungi.)Take cutting, sterilize cuttingDip cutting in rooting hormonePlace one in agar with rooting hormone, and the other in agar without hormone (label!)

Auxin in the Root

Auxin falls with gravity to the lower side of the shoot and root

In the shoot it causes cell elongation, shoot grows up towards the light

In the root it stops the cells elongating, and therefore the root bends down towards the soil and water

Explain what is happening in each experiment and why.

Apical DominanceHigh concentration of axuin in tip (apical meristem) of tree prevents growth

Concentration decreases towards base of tree

Adaptive advantage because the top leaves do not shade the leaves underneath

Resulting in Xmas tree shape

Online ActivitiesComplete the prequiz, watch and read the animation, complete the post quiz did you improve?

NCEA Question

Padlet your answer here

TropismsPlants grow in response to stimuli

Growth towards positive

Growth away from negative

Tropic ResponsesExperiment 1: Phototropic ResponsesAim: To investigate phototropic responses in bean plants

Method:Soak beans over night to encourage germinationCelleotape bean into small boxCut a hole to let the light in on one side of the boxLeave for 5 days open and investigateResults:What is the adaptive advantage of this type of response? What is the stimulus causing the response? What is the name given to this type of response?Experiment 2: Geotropic Responses

Aim: To investigate the geotropic responses in bean plants.

Method:Soak beans over night to encourage germinationScellotape bean into petri dishBlue tack dish vertically onto the wallLeave for 3 days take a photograph Turn petri dish 180Repeat steps 4-5 2 x

Results:What is the adaptive advantage of this type of response? What is the stimulus causing the response? What is the name given to this type of response?Experiment 3: Phototropic ResponsesAim: To investigate phototropic responses in mustard/wheat/grass shoots

Method:Set up a man as seen in picture

Results:What is the adaptive advantage of this type of response? What is the stimulus causing the response? What is the name given to this type of response?

Tropisms1. Why do plants need to respond to the environment?

2. What things can stimulate plants to respond?

3. What does tropos mean?

4. Give a definition and example of the following (try and find a photo to insert as well)- Table as google doc remember to make a copy!

TropismDefinitionStimulusExamplePictureAdvantagePhototropismChemotropismGravitropismThigmotropismHydrotropismHeliotropismTropisms1. Why do plants need to respond to the environment?

- so they can survive, grow and reproduce, make the most of resources

2. What things can stimulate plants to respond?

gravity, light, chemicals, touch, water

3. What does tropos mean?

- Turn

TropismDefinitionStimulusExamplePictureAdvantagePhototropismGrowth in response to lightLightSunflower moving to face the sunIncreased light so increased photosynthesisChemotropismGrowth in response to chemicalsChemicalsPollen tube growing towards ovariesPollen can fertilize egg in safe protected place for reproductionGravitropismGrowth response to gravityGravityRoots growing down into the ground, shoots growing up against gravityRoots gain anchorage, growth towards water, Shoots grow towards light for p/sThigmotropismGrowth response to touchHard surfaceGrape vine curling around a stakeGrowth up towards the light for photosynthesisHydrotropismGrowth response to waterWaterWillow roots growing into river banks

Get water for photosynthesis, transpiration and turgityHeliotropismTracking the path of the sunLight sourceSunflower moving to face the sun

Increased light so increased photosynthesis

The shoot responds to gravity by growing upwards (negative geotropism) and upwards towards the light (positive phototropism)

Auxin is a hormone, that is produced in the tip (apical meristem), IAA is an example, causes cell elongation by making the vacuole retain water. Auxin moves down from the tip causing cells to elongate and grow upwards.

Gravity causes the shoot on sprouting from the seed to grow upwards, if it needs to curve to do this auxin is released to the lower side (gravity drops it to this side) elongating the cells on this side causing the shoot to bend upwards and grow up and out of the soil

Once exposed to light auxin...


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