A comprehensive six page worksheet aimed at advanced biology students, this resource tells the story of how the work of several scientists ultimately led to the discovery and understanding of DNA. The worksheet includes diagrams, images and information relating to classic experiments performed by scientists (including Friedrich Meischer, Fred Griffiths, Oswald Avery, Alfred Hershey, Rosalind Franklin, James Watson and Francis Crick.

A resource aimed at GCSE (14-16 year old) biology students, this worksheet provides a labelling task for animal and plant cells as viewed down the light microscope along with mix and match task relating to the function of each organelle. The task also includes some extension questions on the nature of mitochondria for students to research (perhaps as a homework exercise). The resource is tailored to the Hodder AQA 9-1 Biology textbook but the page references in the worksheet could easily be adapted to any other textbook reference.

A worksheet starter task aimed at GCSE (14-16 year old) biology students. The worksheet consists of six questions related to the topic of mitosis whereby students are required to sort diagrams showing different stages of cell division and describe key events.

A resource aimed at GCSE (14-16 year old) biology students, this resource consists of a series of instructions for four food test investigations (testing for a reducing sugar, protein, starch and fat), each of which can be printed out and positioned at various locations/work stations in a laboratory. The resource also contains a worksheet for students to fill in as they complete each investigation - students should test a known sample of a food substance first in order to see for themselves the positive result/colour change before then testing an unknown mixture.

A resource aimed at advanced level biology students (or high ability GCSE students) that provides questions on how different limiting factors affect the rate of photosynthesis. The emphasis is on interpretation of rate of reaction graphs, with logical reasoning being used to identify and explain the main limiting factors. Answers to all the questions are provided on the second page of the worksheet. Key words: limiting factor, photosynthesis, graph, plateau, temperature, carbon dioxide concentration, light intensity

A worksheet aimed at advanced biology students, this worksheet is ideal as a starter task (or alternatively as a homework preparation/background reading exercise) that covers the reasons why meiosis takes place and the nature of gametes produced from meiosis. This is a useful exercise to conduct with students to establish the 'big picture' prior to study of individual stages of meiotic cell division. Keywords: meiosis, chromosomes, interphase, prophase, metaphase, anaphase, telophase, haploid, diploid, reduction division, independent assortment, variation, genetic, evolution

A comprehensive six page worksheet aimed at advanced biology students, this resource deals with all the major aspects of how a nerve impulse originates and is propagated along a neurone. The worksheets include diagrams that show the different open and closed positions of sodium and potassium channels with space for students to show their own positions of the relevant ions (this is with reference to an online animation - weblink included on the worksheet). The worksheet also has a labelling exercise for the classic action potential graph as well as details on saltatory conductance and factors affecting speed of impulse transmission. Key words: nerve, neurone, depolarisation, repolarisation, refractory period, action potential, resting potential, sodium, potassium, diffusion, ATP, ATPase pump

A resource aimed at advanced level biology students, this resource provides fifteen questions which require students to respond with the appropriate term relating to their understanding of meiosis. Useful as a starter or plenary exercise to consolidate understanding. Key words: meiosis, mitosis, diploid, haploid, homologous, chromosomes, cells, gametes

A worksheet aimed at advanced biology students, this resource contains a number of exercises that require students to make measurements from diagrams and calculate magnification. The exercises also require changing the subject of the magnification formula to work out real size of cells and using a scale bar to calculate magnification. Finally. there are questions about the nature of magnification and resolution and the electron microscope.

A worksheet aimed at biology students aged 14-18 years, this resource provides a series of prompts and questions to help students plan an investigation into osmosis. The practical investigation is a classic one involving potato chips and different concentrations of sucrose solution - the worksheet asks students to consider the variables involved, the range and concentrations of sucrose solution required and then asks students to produce a written plan based on these considerations.

A resource aimed at advanced biology students, this worksheet provides a written schedule for the extraction of chlorophyll from leaves followed by analysis via chromatography. Rf values for various pigments are included in a reference table (including chlorophyll a, chlorophyll b, phaeophytin, xanthophyll and carotene); students can attach their chromatograms to the worksheet, calculate Rf values for each pigment and identify using the reference table. This is a good practical exercise to cover at the start of a topic on photosynthesis, and emphasises the fact that various pigments are responsible for harnessing light energy during the light dependent reactions. Key words: Light dependent, chlorophyll, Rf value, chromatography, chromatogram, solvent front, extraction, leaf, phaeophytin, xanthophyll, carotene, absorption spectra, action spectrum

A worksheet aimed at advanced level biology students, this resource provides a lengthy written passage about the structure and function of cell organelles. The worksheet provides a useful written summary of organelle function in eukaryotic cells for student's revision notes but also requires students to process this information in order to label a diagram of animal cell ultrastructure and explain differences between animal and plant cells.

Biology students often struggle to calculate rates of reaction from graphs. This worksheet provides an explanation of how to calculate rates of reaction from graphs followed by two practice examples. This is a useful worksheet to use as preparation for any practical investigation that will require this skill with data analysis.

A resource aimed at advanced level biology students, this worksheet leads students through an area that often causes difficulty - interpreting evidence for the Calvin Cycle. The worksheet looks at the classic experiment performed by Melvin Calvin that provided evidence for the sequence of events that occurs in cyclic photophosphorlyation or the light-independent reactions of photosynthesis. The worksheet introduces the idea of radioactive tracers and asks students to predict the effect of switching lights off or reducing carbon dioxide levels. Graphs are shown recording the levels of RuBP and GP in response to these changes. Answers to each question are provided on the second page of this worksheet Key words: Light independent reaction, cyclic photophosphorylation, ATP, RNADP, glycerate - 3- phosphate, triose phosphate, ribulose bisphosphate, ribulose phosphate, light dependent reaction, calvin cycle

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 worksheet with method and subsequent questions (including a higher ability challenge question) on the effect of lipase and bile salts on the breakdown of fat present in milk. A good practical activity for GCSE and A-Level students alike, which demonstrates the impact of bile as an emulsifying agent. Key words: phenolpthalein, milk, ph, bile, fat, triglyceride, temperature, lipase

A resource aimed at Advanced Biology students, this worksheet provides a list of questions related to understanding the events of the cardiac cycle. The questions focus on the characteristic pressure change graph that shows AV valves and semi-lunar valves opening and closing as pressure of blood between artery, atria and ventricles changes. Students often struggle to articulate the difference in pressure as the cause of valves opening and closing; these questions will help to reinforce key concepts. Key words: artery, ventricle, atria, semi-lunar, atrio-ventricular, pressure

A worksheet to review the basics of the carbon cycle, identify carbon sources and sinks and review the main causes of increasing carbon dioxide in the atmosphere. Key words: Carbon cycle, source, sink, trees, photosynthesis, respiration, fossilisation, combustion, decomposition, greenhouse, global warming

A worksheet aimed at advanced biology students, this resource consists of four multiple choice questions designed to test understanding of A,B,O blood group genetics and inheritance.

A resource aimed at advanced biology students, this worksheet provides a template for students to work through Gregor Mendel's classic pea breeding experiments showing the results of the genetic cross. The template includes prompts for students to set out their working clearly, showing parental phenotype, genotype, gametes and offspring genotype and phenotype. The second page of the worksheet provides a template for students to work through an analysis of Gregor Mendel's actual results using the chi-squared test. A data table is included in order to determine whether results are significant or not; note that this is one of the rare cases where non-significance (between observed and expected data) actually lends weight to a theory - Mendel's results are not significantly different to those proposed by his theory. Key words: Mendel, genetics, pea, breeding, cross, diagrams, monohybrid, chi-squared, statistics, observed, expected, data