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Lesson Area of specification covered

Links with past topics GCSE/AS level

Focus questions Misconceptions Key vocabulary

1 10. Explain that the numbers and distribution of organisms in a habitat are controlled by biotic and abiotic factors.

11. Describe how to carry out a study on the ecology of a habitat to produce valid and reliable data (including the use of quadrats and transects to assess abundance and distribution of organisms and the measurement of abiotic factors, e.g. solar energy input, climate, topography, oxygen availability and edaphic factors).

12. Explain how the concept of niche accounts for distribution and

Ecosystem

Ecology

What affects the distribution and abundance of species in a habitat?What is the difference between valid and reliable?What is succession?How important is the role of pioneer species in succession?Describe what you would see in a climax communityWhat is the difference between secondary succession and deflected succession?What is a niche?

Which sampling method to use: transect/quadrat

Which method to use to measure abundance and distribution

Explaining what is a niche

SuccessionHabitatNicheCommunity Biosphere EcosystemPopulationSpeciesBioticAbioticEdaphic

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abundance of organisms in a habitat.

13 Describe the concept of succession to a climax community.

2 7. Carry out calculations of net primary productivity and explain the relationship between gross primary productivity, net primary productivity and plant respiration.

8. Calculate the efficiency of energy transfers between trophic levels.

Ecology Do plants store all the glucose it produces?Why is net primary productivity less than gross primary productivity?Why is some energy lost from one trophic level to the next?Why is the role of decomposers important in increasing the efficiency of energy transfer?How can you increase the efficiency of energy transfer?How do you calculate efficiency?

Explain what is energy stored a biomass?

Difference between gross and net

Does all the sunlight which falls on a leaf get absorbed by the chlorophyll?

Food chainFood webTrophic levelConsumersHerbivoresCarnivoresDecomposersProducersGPPNPPEnergyRespiration Efficiency

3 and 4 14. Outline the causes of global warming- including the role of greenhouse gases (carbon dioxide and

GCSE global warming

Greenhouse

What is the difference between global warming and the greenhouse effect?How do the greenhouse

Explaining the difference between global warming and greenhouse effect

Global warmingGreenhouse effectCarbon dioxideMethane

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methane) in the greenhouse effect

18. Analyse and interpret different types of evidence for global warming and its causes (records of carbon dioxide, temperature records, pollen in peat bogs and dendrochronolgy) recognising correlations and casual relationships

effect

Carbon cycle

gases stop infrared radiation from escaping?What would be the consequence of any change in the level of greenhouse gas? How are greenhouse gases produced?Does a correlation mean a cause?How can you use carbon dioxide and temperature records to show evidence for global warming?Why can you use pollen grains as evidence for global warming?How is the width of tree rings related to their conditions of growth?

How does analysing peat and tree ring studies show evidence of changing climate

DendrochronlogyCorrelationsPeat bogPollen

5 14. Outline the causes of global warming- including the role of greenhouse gases (carbon dioxide and methane) in the greenhouse effect

GCSE global warming

Greenhouse effect

Activity 5.12: what are the different parts of the model corresponding to?Is your conclusion valid?What are the limitations to this model 5.12?Why are climate models

Explaining the difference between valid and reliable data?

If one measurement of temperature does not fit the pattern, do you disregard the

Global warming Greenhouse gas Greenhouse effect Climate modelExtrapolationFactorsReliability

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19. Describe that data can be extrapolated to make predictions, that these are used in models for future global warming, and that these models have limitations

Carbon cycle being used?How can climate models be used to make predictions? What are the problems of using climate models?Why is it difficult to make an accurate prediction?Explain how other variables affect global mean surface temperature?What assumptions are you making when you are extrapolating data?

whole set of data? Can there be an explanation for this?

Drawing lines to extrapolate data

Explaining how the different factors on page 45 affect the temperature (activity 5.16, q4)

Carbon dioxide Trends Validity

6 20. describe the way in which scientific conclusions about controversial issues, such as what actions should be taken to reduce global warming or the degree to which humans are affecting global warming, can sometimes depend on who is reaching the conclusions

GCSE:Case study: creating arguments and reaching a conclusion based on the evidence

Activity 5.13: describe some strong data which proves a link between carbon dioxide and global warmingWhy is there controversy surrounding the issue of global warming?Why can the same data be interpreted differently by different people? Give some examplesHow can you use the discrepancies between surface

How to identify weaknesses in data/strong data (5.13)

Why there is controversy surrounding the issue of global warming

Explaining how the same data can be interpreted in different ways.

ControversyEthical argumentTheoryEvidence predictions

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temperature and upper air temperature to justify the case of global warming?What impact do sulphate particles have on climate fluctuation?What are the evidences for global warming and how do they prove a link?

7 16. Explain the effect of increasing temperature on the rate of enzyme activity in plants, animals, micro-organisms

GCSEEnzymes, Rates of reaction

Use scientific explanation to explain your hypothesis.What are the hazards associated with this experiment and what are the precautions you will take?How have you changed your method after conducting the preliminary experiment and why?How did you ensure that the data you collected was valid?How do you know that your data is reliable?How did you decide whether or not you had any anomalous results?Explain why you may have got some anomalous results.

When carrying out risk assessment also thinking about the products being produced and how best to dispose of the products.

Have they chosen a good range of temperatures which will allow them to see a clear pattern and make a strong conclusion about what is the optimum temperature?

Ensuring that the catalase, hydrogen peroxide reach the desired temperature before

HypothesisHazardsPrecautionsVariablesRangeValidReliableAnomalousLimitations

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What are the limitations of the method used?How can you improve the method and how will this affect the results?How does temperature affect the enzyme activity of enzymes found in animals and microorganisms? Give examples

starting experiment.

Why students shouldn’t swirl the boiling tube during the experiment, or make sure they do swirl in all temperatures

8 17. Describe how to investigate the effects of temperature on the development of organisms (e.g. seedling growth rate, brine shrimp hatch rates)

Planning experiments

What are the ethical issues arising from the use of living organisms?How have you considered the well being of the organisms used? How did you ensure that the data you collected was valid?How can you ensure that the results are reliable?What other factors could affect the hatching success? Why?What is the difference between random errors and systematic errors?What are the random and systematic errors that can arise from this experiment?How does this experiment help to prove the effects of global warming?What impact has climate change

What impact is the temperature having on the life cycle of the organism and how does this link in with climate change?

To be aware that it may not be possible to control all the variables.

Random errorsSystematic errorsEthical issuesValidReliableLife cycleClimate changePhenology

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had on the development of organisms? give specific examples What are the problems with eggs hatching too early?

9 15. Describe the effects of global warming (rising temperature, changing rainfall patterns and changes in seasonal cycles) on plants and animals (distribution of species, development and life cycles)

Enzymes How will an increase in temperature affect the rate of photosynthesis?Why does the rate of photosynthesis affect the development of plants?Why will the distribution of species be affected due to climate change? What problems may this give rise to?What will be the affect of pests and diseases spreading to different areas?How might plant species be dispersed to a different area?Comment and explain on the time taken for a species to distribute to another area?What are the problems with eggs hatching too early?

The effect on photosynthesis if the temperature increases above the optimum temperatureIs temperature the only limiting factor when it comes to the rate of photosynthesis

The effect of shorter life cycle on other organisms and availability of food.

The effect of species distribution on the current inhabitants.

DominantDistributionDispersalCompetitionRateEnzymesLife cyclePhotoperiod Development

10 21. Describe how evolution (a change in the allele

Mutation

Evolution

How can allele frequency change over time?What is natural selection?

Explaining evolution using key concepts

EvolutionNatural selectionProteomics

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frequency) can come about through gene mutation and natural selection.

23. Describe the role of the scientific community in validating new evidence (including molecular biology, e.g. DNA, proteomics) supporting the accepted scientific theory of evolution (scientific journals, the peer review process, scientific conferences).

Natural selection

Why is it important to present scientific findings in conferences?What are the advantages and disadvantages of publishing scientific ideas directly online?What are reasons for having a paper peer reviewed? How has genomics and proteomics provided evidence for evolution?What are the different types of molecular evidence supporting the theory of evolution?

Why should ideas be peer reviewed?

GenomicsPeer reviewDNA Hybridization DNA profiling DNA and protein sequencingDNA molecular clocks

11 22. Explain how reproductive isolation can lead to speciation

Natural selection

Define speciesWhat is reproductive isolation?What is the impact of having individuals separated by a geographical feature?Why might the individuals face different selection pressures?Will the evolution of both the populations be the same?What are the reasons why two species may not be able to interbreed?

Why two populations may face different selection pressures?

Why may the two populations be unable to interbreed, which is a consequence of the random mutations accumulating

Writing long answer questions on speciation

SpeciationReproductive isolation TemporalEcologicalBehavioural Physical incompatibilityHybrid inviability Hybrid sterility

12 9. Discuss how Carbon cycle What are the ways in which carbon is incorporated into the

Is the transport of biofuels carbon neutral?

PhotosynthesisRespiration

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understanding the carbon cycle can lead to methods to reduce atmospheric levels of carbon dioxide (including the use of biofuels and reforestation).

atmosphere?What are the ways in reducing the amount of carbon from the atmosphere?Is there a balance?What is the reasoning for using biofuels for maintaining carbon dioxide?Is using biofuels an effective solution?Why may different countries differ about the views on biofuels?How can we maintain the carbon dioxide balance by reforestation?Will reforestation really work? Why?

How much carbon dioxide can the trees take in, is there a limit to the rate of photosynthesis?

Decay / decomposition, BiomassCombustionCarbon sink Deforestation Reforestation BiofuelBiogas

13 2. Describe the structure of chloroplasts in relation to their role in photosynthesis.

3. Describe the overall reaction of photosynthesis as requiring energy from light to split apart the strong bonds in water molecules, storing the hydrogen in a fuel (glucose) by combining it with carbon dioxide and releasing oxygen into the

Chloroplast function

photosynthesis

How are the thylakoid membranes adapted for the light dependent reactions?How is the stoma adapted for the light independent reactions?Why are starch grains present in chloroplasts?What is the role of hydrogen in photosynthesis?What is NADP?What is the difference between reduced NADP and NADP?Explain what is meant by the

Where are the enzymes located for the light dependent and independent stages

What is NADP and how does it become reduced

Main products needed for light independent stage is reduced NADP and ATP

Carbon dioxide and water

PhotosynthesisMicroscopeChloroplastStromaThylakoidATPHydrogenReductionNADPEnzymes

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atmosphere. reduction of carbon dioxide? have no direct contact

14 4 Describe the light-dependent reactions of photosynthesis including how light energy is trapped by exciting electrons in chlorophyll and the role of these electrons in generating ATP, and reducing NADP in photophosphorylation and producing oxygen through photolysis of water.

5. Describe how phosphorylation of ADP requires energy and how hydrolysis of ATP provides an immediate supply of energy for biological processes.

Chloroplast function

Photosynthesis

Reduction

ATP

What are the useful products of the light dependent reaction?How is light involved in this first stage?Has any glucose been produced at this stage?What does the electron transport chain consist of?How will the electron transport chain be affected if one of the carriers had a mutation?What will be the result if all the coenzyme NADP were reduced?How will the reaction be effected if no water was available?What is needed for the photolysis of water? Is an enzyme involved?Why is ATP an important energy transfer molecule?What happens during the phosphorylation of ADP?How does the hydrolysis of ATP provide energy?

If no NADP were present the electrons would not be accepted from the electron transport chain and it will stop

NADP must be regenerated from reduced NADP

Electrons must from the splitting of water must replace the electrons lost from the chlorophyll

Enzyme ATPase involved in hydrolysis of ATP

The role of water molecules in releasing energy (hydrolysis of ATP)

Photophosphorylation ATPHydrolysisPhotolysisExcitedPhotosystemElectron transport chainNADPLight dependant reactionEnzymes ElectronHydrogen

15 4 Describe the light-dependent reactions of

Chloroplast function

What is the name of the molecule reduced in the light dependent

What is a reducing agent? What happens to the

DCPIPReducing agent

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photosynthesis including how light energy is trapped by exciting electrons in chlorophyll and the role of these electrons in generating ATP, and reducing NADP in photophosphorylation and producing oxygen through photolysis of water.

photosynthesisstage?What is a reducing agent?Will DCPIP decolourise if left in the dark?Will DCPIP decolourise if there is no chloroplast in the tube?If DCPIP changes colour what does this show? Where have the electrons come from?What molecule involved in photosynthesis is DCPIP behaving like?How will the light dependent stages of photosynthesis be affected if no carbon dioxide was present?

reducing agent?

DCPIP is behaving like NADP

Tube containing chloroplast and DCPIP in the light should decolourise

Electron acceptorLight dependent reaction

16 6.Describe the light-independent reactions as reduction of carbon dioxide using the products of the light-dependent reactions (carbon fixation in the Calvin cycle, the role of GP, GALP, RuBP and RUBISCO) and describe the products as simple sugars that are used by plants, animals and other organisms in respiration

Chloroplast function

photosynthesis

What is carbon fixation?Where is ATP needed in the Calvin cycle?Can the cycle occur in the absence of reduced NADP?What is the role of enzymes in the Calvin cycle?How does ATP provide energy for the reactions?Can the cycle continue in the dark? Why?What are the products of the light independent stage and what are

How will the other products in the cycle be affected if one of the enzymes has a mutation?

The cycle cannot occur without the products from light dependent reaction (ATP, reduced NADP)

Understanding the numbers of carbon atoms involved in the cycle

Carbon fixationEnzymeGPGALPRuBPRUBISCOATPReduced NADPSugarsPhosphorylation

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and the synthesis of new biological molecules (including polysaccharides, amino acids, lipids and nucleic acids).

their uses?What will happen to the number of RuBP if there was a mutation in enzyme RuBISCO?How will this affect the rest of the cycle?