A quiz that asks students to give the correct word that matches each description. Useful as a recap of key vocabulary. The worksheet also contains an extension question based on quadrat sampling where students are asked to calculate population density of a plant species.

A worksheet of questions related to the nitrogen cycle which students are required to research. Each series of questions is divided into separate categories according to which part of the cycle they relate to: nitrogen fixation, nitrification, ammonification, denitrification, etc. A useful worksheet to issue at the start of a topic as background research for students to gain familiarity with the key ideas. Keywords: Nitrogen, cycle, ammonifiication, denitrification, nitrification, saprobiont, decay, fixation

An activity aimed at A-Level Biology students. This activity involves a series of statements that can be given to a class at the start of a lesson with the instruction that they draw the nitrogen cycle based on this information. Students should initially do this in pairs but can then be teamed up in larger groups to show, discuss and explain their own diagrammatic interpretations of the nitrogen cycle. Finally, the whole class can be brought together to discuss the best way of joining these statements together into an agreed nitrogen cycle. Key words: Nitrogen, cycle, ammonification, nitrification, denitrification, saprobiont, decay, symbiotic, rhizobium, azotobacter, decomposition, photosynthesis, respiration, combustion, fossilisation, assimilation, feeding, herbivore, carnivore, carbonate

An activity aimed at A-Level Biology students. This activity involves a series of statements that can be given to a class at the start of a lesson with the instruction that they draw the carbon cycle based on this information. Students should initially do this in pairs but can then be teamed up in larger groups to show, discuss and explain their own diagrammatic interpretations of the carbon cycle. Finally, the whole class can be brought together to discuss the best way of joining these statements together into an agreed Carbon Cycle. Key words: Carbon, cycle, decomposition, photosynthesis, respiration, combustion, fossilisation, assimilation, feeding, herbivore, carnivore, carbonate, ocean, diffusion

A worksheet aimed at A-Level Biology students that provides four questions to practice their knowledge of the technique of mark-release-recapture. The questions also test student's understanding of the limitations of this technique and causes of inaccuracies Key words: Mark, release, recapture, biology, limitations, assumptions, N1, N2, n, population, estimate

A worksheet aimed at A-Level Biology students that looks at various examples of restriction enzymes and whether they are suitable for cutting out a gene from a sequence of DNA. Students must look carefully at the restriction recognition sequence for each enzyme and decide whether it is suitable for removing the gene. This is based on whether the recognition sequence occurs in the middle of the gene or at the ends and whether the enzyme will leave blunt or sticky ends. Key words: Restriction, enzyme, blunt, sticky, gene, DNA, EcoR1, HindIII, BamH1

This worksheet is aimed at A-Level Biology students and covers the principles of restriction mapping of plasmids using restriction enzymes. This is often a difficult topic for students to understand, but this worksheet covers the basic principle, worked examples and also provides some questions for students to practice the principles. Key words: Restriction, enzyme, plasmid, mapping, kilobases, DNA, base pairs, restriction site, fragment, electrophoresis

A worksheet aimed at A-Level Biology students that requires students to read a passage of text, study diagrams and answer questions that require application of knowledge on the Carbon Cycle. The stimulus material is in the context of space science research and mapping of the Earth's oceans. Phytoplankton are a major carbon sink and their numbers are declining, possibly as a result of global warming. This worksheet considers the implications of this change. Keywords: Phytoplankton, Carbon cycle, space, satellite, envisat, sink. oceans, greenhouse, global warming

A summary worksheet for A-Level Biology comprising three exercises, including calculation of population growth, interpretation of survival curves and interpretation of population pyramids (showing increasing, stable and decreasing population). Key words: Population, pyramid, biology, survival, curves, graph, growth, increase, percentage

A worksheet that reviews the key points about succession in an ecosystem: what it is, how it happens, sequence of events, factors affecting and different types. The worksheet also has a question on diversity index in a mown and unmown lawn as an example of deflected succession. Key words: Succession, diversity, climax, community, grass, shrubs, pioneer, species, trees, index, primary, secondary, deflected

A worksheet that uses a respirometer as an example of a spearman rank exercise. Students are required to analyse the data provided to see whether there is any correlation between temperature and oxygen consumption. Key words: Spearman Rank, temperature, respirometer, oxygen, correlation, consumption, null hypothesis, probability

A quick test comprising four questions on mark-release-recapture, use of random sampling with quadrats and chi-squared statistical analysis. Useful at the end of a series of lessons on ecology as a quick review of key principles. The assessment includes answers to all the questions. Key words: chi-squared, mark-release-recapture, random sampling, quadrats, ecology, test, exam, answers, quiz

A worksheet that provides secondary data from an investigation into the population density/abundance of plant species in a field. The worksheet requires some calculations to estimate population density and total population size across the whole field. There is also consideration of the reasons why quadrats are always deployed randomly and why random sampling is required for any fieldwork investigation. Key words: quadrat, fieldwork, dandelions, daisies. estimate, population, density, abundance, calculations

A worksheet aimed at A-Level Biology students that compares and contrasts pyramids of number with pyramids of biomass. The worksheet requires students to perform simple calculations of total biomass and consideration of the pyramid shapes that result. Key words: biomass, number, pyramid, energy, loss, efficiency

A worksheet aimed at A-Level Biology students which sets out a series of research tasks for students to learn about the nitrogen cycle. A good resource to use at the start of this topic as homework or in class by dividing out each piece of key research among the class. Internet websites are listed which provide useful animations and information for students to use as they complete their research. Key words: nitrogen cycle, deamination, ammonification, denitrification, nitrification, nitrogen fixation, nitrogen, ammonia, nitrite, nitrate, ammonium ions, symbiotic

A worksheet aimed at A-Level Biology students which provides a neat summary of the key points in the Nitrogen Cycle. The resource covers naming of key compounds (nitrate, nitrite, ammonia, ammonium ions), deamination, ammonification, decomposition and denitrification. The resource also has two 'challenge' questions for more able students to apply their knowledge. Key words: Nitrogen cycle, ammonia, nitrite, nitrate, ammonium, deamination, ammonification, decomposition, denitrification

This worksheet is designed to work with the web-based world mapper resource - an ingenious programme that distorts the world map according to the prevalence of certain factors. For example, if cholera deaths was the selected factor, Africa would be hugely increased in size on the map, whereas North America would shrink to become almost invisible. This worksheet allows students to see the impact of various factors of their own choosing on birth rate, death rate and overall population size. A great way for students to find out for themselves how various factors affect the global population. Key words: Population, geography, death rate, birth rate, disease, economics, religion, biology, map, world, earth, continent, countries, europe, north america, south america, asia, oceania

A summary worksheet that simplifies information required for two statistical tests: chi-squared and 95% confidence limits + standard error. The first pages of the worksheet focus on the need to conduct statistical tests and an understanding of what the mean and standard deviation tells us about data. Key words: standard deviation, mean, chi squared, 95% confidence limits, standard error

A worksheet for A-Level Biology students, for use after the main statistical tests have been taught. Students often learn statistical tests by rote, but lack the independence of thought to select appropriate statistical tests for an investigation they have designed. This worksheet provides various examples of possible titles for quick and simple investigations that can be done in the space of a lesson or for homework - students must then select the appropriate statistical test to analyse their results. Key words: Statistics, Chi-squared, 95% confidence limits and standard error, spearman rank, independent, investigation, biology, A-Level

A worksheet aimed at A-Level or high ability GCSE biology students, looking at the different trophic levels found in a typical food chain and the reasons why energy is lost at each level. The worksheet also introduces percentage efficiency calculations when calculating energy loss. Useful as either an introduction at the start of this topic or as a revision activity. Key words: Energy, trophic levels, food chains, percentage efficiency, respiration, photosynthesis, decomposers, kilojoules