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Misconceptions in Science

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CONTENTS

Page no.

Misconceptions Cells 2

Interdependence 3

Particles 4

Forces 5

Energy 6

Sc2,3,4 7

Models and Analogies Models 8

Analogies 9

Models & Analogies 10

Identifying Misconceptions

Using Bloom’s Taxonomy

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The 4 W’s 18

Developing Questions

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Poems 21

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Misconceptions regarding:

CellsAll different70% waterCells are like bricks all have wallsCells and particles being confusedFlatLinks between generalised/specialised cellsVacuole (vacuum) Where energy come from in cellsAll cells are the same shapeAlive?Abstract idea of cell?Other uses e.g. physics, biology, prison!3D model - see as 2D – microscopesThe nucleus is the brain that controls the cell, same as atomStain-blue/purple – no idea why. Think that Brain cells are purple because of the stainOnly animal cells have membranesSemi-permeable – cell membrane2 dimensionalNo concept of sizeCells are as small as atoms.Lack of knowledge rather than misconceptions

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Life and Energy Transfers (Interdependence)

Arrows in food chain represent what eats what, not energy transferArrows wrong way roundFood chains/webs rarely isolatedEnergy being lost through food chainAs the mass of the animal increases, the amount of energy passed along the food chain decreasesRespiration – animals and breathingBiomass/numbersDefinition of HABITAT‘Pyramids’ of different shapesFood chains begin with plant materialFood web confusionOnly top consumers are predatorsHerbivores and vegetarians are the sameNo clear view of what an animal isHumans – animals – we are not animalsTaxonomic groups – can’t distinguishIf it lives in water and swims it must be a fishPhotosynthesis – process Visualising gases going to leaves More logical to absorb nutrients through soilPlants make food at night and respires at nightWater enters plants through leaves “excrement” and egestionAll plants have flowersWhen something dies it is gone-no cycling of energy

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ParticlesSmaller as they gain more energyParticles are solid ballsAtoms and cells the sameConfuse elements, molecules (terminology)Size of particles – expand as heat appliedExpand or get squashedParticles change with changes of stateParticles do not change state themselvesBondsPressure and particlesCan’t believe everything made of particlesDon’t change sizeGases are airspacingAir has weightVacuums/sucking /blowingSurface area/particle sizeMelting = dissolvingMelting point and freezing point sameLanguage-diffusionConceptually difficultParticles moving at same speed in a liquidPupils think there is air between nucleus and electronsParticles further apart in a liquid than a solidFreezing point is different to melting pointParticles expand when heatedParticle arrangement in liquidsParticles disappearParticles ‘melt’Particles are the same size as cellsLiquids cannot be compressedEvaporationThicker liquid because more particlesParticles expand to fill up gapsCloser together traps heatRoom temperature can get inBehaviour of particles different in different materialsParticles like the earth – hot coreHeat as a particle/substanceAir in and out of particlesHeat lets it cool downAttributing human attributes to particles Particles stop moving when frozenCan’t compress liquidsWrong ideas of crystalliseChanges of state not connectedNo links between gases and liquids

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ForcesObjects stop moving when force runs out, slowing moving objects (‘run out of push’)Balanced-difficult for constant speedSpeed and velocityForce/pressure the sameNo forces acting on stationary objectsForce and motionConfusion between mass and weight/air pressureForce and pressureConcept of frictionBalanced forces when movement taking placegravityNo gravity in spaceObjects moving at constant speed have no resultant force acting on thempressureDensity-Dense=heavyAct at a distantNon contact forceStill working in space Different masses accelerate at different rates in a vacuum No gravity anywhere but on Earth – you don’t weigh anything on the moon

Moon /earth/gravityEqual/opposite – reaction?Bigger the object – faster it fallsOpening parachute goes up/slows downLight year(time)Thin=weak and thick rope =strong – lighter materials can’t be strongerTerminology(eg proportional)

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EnergyMaking energyEnergy is used up – not convertedWhat is it? – Abstract conceptWasted?Is a substance (fuels react with heat)Can disappear or doesn’t disappearDissipation rather than destructionComes from somewhereSpectrum of light – absorbtion of lightTypes/forms?Created/destroyedPhotosynthesisEndo/exothermicDifferent forms of energy water, wind, coal/electricityRenewable/non renewable – mark schemes of acceptable termsHeat and temperature are the sameCan’t have it both ways. Common teaching and realitySeries/parallelElectricity – big problem- force of energyConfusion about the ways of generating electricity and forms of energyElectricity is used up in a circuitConfusion force/energy/nuclear energyHeat ‘rises’Abstract concept of radiation being electromagnetic waveElectricity is a fuel A car burns fuel and uses up energy – noisy car wasting energyWheels make energyVibrations generate heatCar uses fuel (everyday language)Law of conservation of energy

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Further misconceptions from:

Sc2, 3 & 4

Sc2Fertilisers are plant foodRespiration is the same as breathingPlants don’t respirePlants only respire at nightPlants get their food from the soilThe nucleus is like a brain (nucleus of an atom)Plants breathe in CO2, animals O2

Respiration takes place in the lungsOnly mammals are animals

Sc3Alkalis (the opposite of acids) aren’t dangerousDissolving is the same as meltingWeathering is the same as erosionRocks can be broken by freezingParticles can be broken by freezingParticles expand on heating All metals are magneticSalts are the same as salt (NaCl)Materials are just textiles/building materialsParticle same as visible grains e.g. in rocksAir is good gas is bad

Sc4Shining objects are sources of light.Clashing current theoryCurrent is used up in a circuitEnergy is a material and has a mass (like a Mars Bar)Heat is the same as temperature.Thermal radiation is the same as radioactivity (radiation).Light travels from the eye.Pitch is the same as loudness.Gravity = ‘downnessParallel beams of light get dimmer the further they travel.When an object is stationary, no forces are acting on it.Heavy object fall faster than light objects.Something stops moving because the force runs out.

GeneralConfusion between microbes/cells/particles

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ModelsBell jar and balloons – Demo breathing systemLoop of rope to show current doesn’t go away – circuit modelRope for current – tight grip.Current – rope around the classroom, pupils hold on and act as bulbs.Making 3D cells.Plastic bag with holes – Pressure in a liquid is the same.Fair testing – diet and exercise.Plastic bag for a cell.Making fossils using plaster of paris.Erosion – water down a shoot with sand in.Solar system model showing rotating planets etc.Rusting showing takes up oxygen:Model arm – when you relax the arm(antagonistic pairs of muscles)

Forces – Straws for bridges.Planets distance – role play on school fieldsPoppy beads break off for starch.Chain beads to represent starch – glucose.

Wet iron filings

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Analogies

Ammeter A little devil counting electronsArteries and veins Rubber and vacuum tubingAtom Centres Football pitch centre circleAtoms Football in the centre of a football pitchLego bricks To show crystals - interlockingDissolving Rice grain between peas.DNA Scrunched up cotton.Electrical CurrentFish swimming through water pipes.Electricity Role play with marbles.

Gas – released from hall.Liquids – Moving from assembly.

Multicellular Multi-national corporations.Nerves Telephone cables.Particles Solids – Assembly;

Pitch with flies flying round the terracesSperm Swimming in an Atlantic of treacle.Turgidity in cells Balloons in a boxUnicellular Own business.Variation Class data.Building Site Specialised cells – bricks roofShared money purchase of car £1000 each share the car -

covalent moleculesKinetic theory modelling

“bouncing about”If your head was the size of the earth … an atom would be the size of a pea.Measure the solar system with metre rules.Distance between electron and nucleus (KS4)Hydrogen atom – electron is a walnut on the head of Nelson (Nelson’s Column) the nucleus is a melon at the column’s base.

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MODEL/ANALOGY USED

WHAT IT CAN EXPLAIN

WHAT IT CAN’T EXPLAIN

WHAT MISCONCEPTIONS IT CAN GENERATE

HOW IT MAY BE IMPROVED

Jelly cells with sweets for organelles.

Perspectives Parts of a cell

Size Diffusion Division

Fixed sealed unit Scale All cells look the same

Colours

Use ICT to back up observations, video microscope.

Many plant cells put together.

Moulds to make different cells – sperm, nerve and blood.

Battery teacher

Rope

Children

Electricity not used up.

Energy transfer. Battery as pushing. Resistance. DC. AC.

Parallel circuits Energy delivery Voltage

Electricity lines have string in them!

Add a spring balance to represent voltage.

3D cells 3D understanding Cytoplasm Memory tool Cell membrane layer Cell wall (2 bags) Nucleus

Relative sizes Functions Specialisation

Practicality (movement through membrane)

No differentiation, all cells are the same

Video/microscopes to back up

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MODEL/ANALOGY USED

WHAT IT CAN EXPLAIN




Poppet beads Digestions of starch Enzymes can not be used up

Breakdown of starch could take place without enzyme

Enzymes are little people pulling molecules apart

Molecules are balls!

Link in to Key Stage 4

More enzymes/ people pulling enzymes apart.

Peas/sand Dissolving Saturation

Temperature Molecules are not dispersed but settled.

Particle size

Solubility – temperature dependence

The digestive system is a long tube that starts with the mouth and ends with the anus.

Unwanted materials pass through the digestive system are lost from the body

That digestion is a very complicated process

The tube is the same diameter all it’s length

There are no connections between other organs

Development of original concept to teach increasing complexity of the process

Bunsen tubePressure tubingSmall bore tubing

Relative sizes of artery, vein, capillary

Blindfolded pupil in room walking and running

Kinetic theory/collision theory –reaction rate

particles have legs Kinetic theory Machine which mechanically moved balls in air as in bingo machine – could you tally the collisions

Two pupils each have £1000 – want £2000 car how can they buy it.

Covalent bonding-sharing of electrons –neither pupil owns car

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MODEL/ANALOGY USED

WHAT IT CAN EXPLAIN




Water pumpInc water wheelInc split pipe

Current isn’t used up can explain energy change

explains parallel current splits

Why cells run out Electricity is stored in the cell.

Actually have a water pump set up.

House=organismHouse wiring=nervous systemBeating heart=pump

Cells building blocks Specific cells Organs

Pea and beach ball Size of earth and sun

Relative distances Relative distances Scale it down – do it outside. Local landmarks.

Model cell(animal plastic bag,wallpaper paste, plasticine nucleus)

3D model of cell how thing get in and out of cell

Tennis ball in stocking leg

peristalsis muscles ‘stretch’ (where bolus is)

Electric current as water flowCurrent in circuit as water through pipes (Cell-pump, water pipes)

Conservation of current & resistance. Cell provides the ‘push’

Why current decreases when you have a parallel circuit

Current is used up Cell pro

Doesn’t lead on to voltage

Why cells run out Energy

Electricity can be stored in the cell. Wires are wide and narrow

Electricity is a substance

Electricity is like water

Keep it very simple. Don’t use a box for a pump, use a waterwheel.

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MODEL/ANALOGY USED

WHAT IT CAN EXPLAIN




Weighing bag of coins in a bank

To explain molecules – don’t find mass of one atom, but a group

How mass of one atom was found originally

That they may imagine that you can actually find mass of one atom using a balance

Stadium - Seated- Standing- Runners

Solids Gases Liquid

How you can get from one state to another

When metals burn they gain weight

Blu tack

Iron wool heated

Metals gain weight when heated

what add on from the air

when metals burn they become heavier than blu-tack

Pigs lungsInflate the lungs when the lungs deflate the air rushes out due to the change of air pressure

the movement of air in and out of the lungs

how air moves into the lungs –inhaling

that the lungs are blown up

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MODEL/ANALOGY USED

WHAT IT CAN EXPLAIN




Visking tubing for digestion.

Enzyme action on starch – to allow it to pass through the gut wall

Products are carried away in the bloodstream

That it can only happen to starch.

A larger scale model to show that some things can pass through, others not.

Using pupils to represent atoms (with coloured hats for different elements). Form bond (hold hands) to represent compounds.

Difference between compounds and mixtures and different numbers of each atom to make compounds

Why they form compounds

Humanizes atoms. They can follow up by down what each bit of the model represents.writing

‘Moshpit’ analogy to represent the heating effect of a current

Resistance – particles movement increasing with heat.

Electrolysis – cards to represent ions

migration of ions to anode and cathode

difficult to explain how electrons travel down cathode/up the anode to complete the circuit

humanizes ions

Who’s got the worst temper

fractional distillation

Evaporation by rugby league tables

evaporation competition reactions

same result every time

No odd results e.g. Charlton winning league

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MODEL/ANALOGY USED

WHAT IT CAN EXPLAIN




ChromatographyPeople (size) + attraction of molecules with solventsSustainable/non sustainable development using the analogy of sprint running and slow jogging

non-sustainable development will lead to environmental/social disaster – good to explain meaning of word “sustainable”

Fat man in a lift (old style lift)

intro to diffusion semi permeable membranes

Particle role play particles movement distances- what a particle is

spaces between particles in a liquid

Solids/liquids/gases use people to model

structure of a solid/liquid/gas

expansion/conduction/convection, dissolving

could appear particles get bigger

Model arm – muscles – elastic bands

antagonistic muscles muscle appears to get tighter

Kids as particles kinetic theory time collisions /transfer of energy

direction of movement/choice

Make kids more bouncy/elastic

Atomic model card etc polystyrene balls

3D nature of atoms movement of electrons

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MODEL/ANALOGY USED

WHAT IT CAN EXPLAIN




Factory, roads, coal, houses to explain electricity

give a more physical example of current, electrical energy, etc in electricity

Lung model – bell jar with balloons

Pressure changes. Diaphragm function and relation to inflation and deflation of lungs

Main structure of lungs/thorax

Rib movement Internal structure of lungs

Gas exchange Wind pipe and link to lungs

Ribs don’t move Lungs are hollow Diaphragm pulled down by something not contraction

Windpipe is a hollow tube

No blood to carry gases to and from lungs

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Using Bloom’s Taxonomy = Developing focused questions

Rocks

KnowledgeWhat are the three types of rock?

ComprehensionHow does water cause erosion?

ApplicationWhy can’t igneous rocks have fossils?

AnalysisRate of cooling is linked to size of crystals, which rocks cool fastest and why (based on size of data)

SynthesisWhat conditions are needed for metamorphic rock to form? Which type of rock would make the best pavement slabs and why?

EvaluationOne unknown sample, one final acknowledgement on sedimentary and analyse.Explain how you might find a seashell fossil at the top of a mountain.

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Focussed Questions

The 4 W’s

What

What are cells?What do you need to see them with?What do the different animal cells do?What is the difference between X and Y?What do they look like?What is it’s job?

Why

Why do we have different cells?Why are cells different shapes?Why are we made of cells?Why are cells small?Why is it that shape?Why are plant/animal cells different?

When

when we grow what happens to cells?When we die what happens to cells?When do cells respire?when do the stomach cells acid?When do they become specialised?When are they formed?When was the term cell first used?When do they die?When are they used?

Where

Where are cells formed?Where are the parts of the cell?Where would you find specialised cells?

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Developing questions about known misconceptions

MISCONCEPTION QUESTIONWater comes in through the leaves and petals.

Why are leaves waterproof?

Water is absorbed through the petals and leaves.

How does water get into the plant?

Flowers absorb sunlight What is the purpose of the flower?

Plant growth is better the hotter the plant is/higher the temperature

Where does the plant make its food?Do all plants have flowers?Where does the carbon come from?Will a plant live well in a hot oven?

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INTERDEPENDENCE

MISCONCEPTION QUESTION TO ASKFertilisers as pesticides What is the difference

between …………Watering the plant not the soil

Would the plant grow if you water the soil.

Heat needed for the plant to grow

In which season does grass grow best.

Petals absorbing water What happens when the petals drop off.

No key words. What is the scientific name for this process?

Keep insects out. When might plants need insects?

Daily watering Does it rain every day?No gas exchange. Why don’t plants grow on

the moon?Kept in a moist place. How do plants grow in a

desert?No products What are they doing

photosynthesis for?Leaves aren’t important. Why don’t plants have

mouths?Water in through petals. What are roots used for?Heat from sun rather than light?

What form of energy do plants get from the sun?

Fertiliser/pesticide What is the difference between fertiliser and a pesticide?

No CO2 or gas What ingredients do plants need to make food?

Site of photosynthesis Why do plants need leaves?

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Poems

1There was a light lady called jouleWho CONSERVES her ENERGY in a poolHer POTENTIAL was SOUNDAnd CHEMICALLY foundHer KINETICS was what made her move.

2ENERGY is measured with the unit JOULEThis powers a fan which keeps you coolThe ENERGY the fan has is KINETICAnd that’s as far as we go, cause we’re pathetic!

3JOULE CONSERVED her POTENTIALTo trip the CHEMICAL LIGHT fantastic.Which SOUNDS rather ENERGETICALLY KINETIC!

4CHEMICAL ENERGY is the best,KINETIC, SOUND, LIGHT and POTENTIAL are the rest.We use it, can’t lose it as its CONSERVEDJOULE is the unit, the man’s experiments were absurd.

5My CHEMICAL ENERGY has turned to KINETICAs I grow more freneticAt the top of the hillMy POTENTIAL is stillTo be CONSERVED as a JOULENo SOUNDS or LIGHT you fool.

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6James Prescott JouleWas nobody’s foolThe praise that he got, he deserved.He switched energy roundLight, kinetic and soundAnd found it was always conserved.

7The energy in light and soundNever goes roundThe joule came from a chemicalConverted it’s potential

8Sound and light are energyKinetic and potential tooBut without any energyWe would not be able to do!

9There are many types of en-ergyKinetic, sound and light to seeThe unit used is the jouleDon’t forget it and be a fool

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10Sound, light, kinetic or chemicalAll energy is conserved even potential

11Potential, chemical, light and soundAre all types of energy that you might have foundIt can be conserved or changed as a ruleIt’s now all measured in the unit of a joule

12You make sound as you move aroundIf the room is bright then that’ll be light

13There was a young lady from PooleWho thought she’d used up a joulePotential was chargedKinetic was blamedBut sound light and heat were conserved

14There was an old gimmer called CrispinWho struggled so much to get jokes inTo the delegates despairThey gave him a oneJust to get him out of their hair.

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