This worksheet is aimed at either GCSE or A-Level students studying microbiology. The worksheet is an ideal lesson starter to use following preparation and incubation of agar plates that have been inoculated with bacteria (from unpasteurised milk in this example, but easily adaptable for any other source of bacteria). The worksheet introduces the idea of binary fission and the concept of a visible colony being made of many thousands of individual bacterial cells. The worksheet also includes an activity on counting bacterial colonies and estimating numbers based on dilutions that would set students up well for a subsequent lesson where they did this activity using their own agar plates. Key words: Agar, bacteria, colony, estimate, milk, pasteurisation, binary fission

A resource aimed at advanced biology students, this worksheet contains a practical schedule for the Hill reaction - a classic practical investigation which provides evidence for the light dependent reactions of photosynthesis. The worksheet contains practical instructions, tables for students to complete with their observations and a list of follow up questions that probes understanding of both the experimental procedure and importance of controls plus the background biochemical theory. The experiment is simple to set up (I recommend using spinach leaves) and straightforward to perform making it an ideal practical to add to what can otherwise be a fairly 'dry' topic. Key words: Hill reaction, NADP, light dependent reaction, light independent reaction, photosynthesis, chloroplast, cells, DCPIP, reduction, colour, expeirment, investigation, control

Suitable for A-Level Biology, this worksheet provides a series of questions suitable for use as a plenary, on the causes of lactose intolerance. The questions make synoptic links with other topics including biological molecules and enzymes. Key words: Lactose, enzyme, hydrolysis, milk, glucose, galactose

A comprehensive worksheet aimed at advanced biology students, this resource provides an initial starter task that focuses on the nature of the genetic code. The worksheet then moves on to consider the nature of genetic disease with a particular focus on sickle cell anaemia and phenylketonuria. Key words: DNA, triplet, code, codon, mutation, sickle cell, phenylketonuria

A resource aimed at GCSE (14-16 year old) biology students, this worksheet consists of nine questions that probe understanding of the process of osmosis. This resource is ideal to use as a starter activity following the classic practical investigation into how different concentrations of salt or sugar solution affect the mass of a potato chip. Key words: osmosis, mass, percentage change, water, concentration

A starter activity suitable for GCSE and A-Level microbiology students, this resource provides a written account of a very badly organised practical session (the misfortunes of 'aseptic Adam'). Students are required to identify the problems in this investigation, explain the problems and solve the problems - ideal as an introduction to an evaluation on student's own investigations if they have recently completed a microbiology experiment. Key words: aseptic, contamination, bacteria, agar, incubate, colonies, evaluate

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.

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 phosphorous 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 phosphorus cycle. Finally, the whole class can be brought together to discuss the best way of joining these statements together into an agreed phosphorous cycle. Key words: Phosphorous, cycle, ATP, NADP, weathering, phosphates, fertilisers, glycolysis, kinase, phosphorylation

A worksheet aimed at advanced biology students who are studying a topic on gene technology and the role of restriction endonucleases. The worksheet consists of task where students are required to choose the most appropriate restriction enzyme to cut out a gene from a piece of DNA. Students are given four different examples of restriction enzymes, together with information about the recognition sequence for each enzyme. Using this information, students must then select the most appropriate enzyme to cut out the gene. Key words: restriction endonuclease, gene, recognition sequence

This guidance sheet is for use in lesson as an introduction to muscles and the features of synovial joints. The dissection is broken up into several different tasks, each of which have follow up/extension questions that encourage students to make cross links with other topics. Muscles, bone, cartilage, ligaments and tendons are all covered in this activity.

A resource aimed at biology students studying surface area: volume ratio. This worksheet discusses the nature of surface area:volume ratio and why it is important in terms of gas and heat exchange in living organisms. The first worksheet covers basic principles of calculating surface area and volume of cubes of varying sizes, followed by calculation of surface area:volume ratio. Unlike many textbook resources, this worksheet emphasises the fact that surface area is linked to the ABILITY to exchange whereas volume is linked to the NEED to exchange. The second worksheet considers how this principle is applied to adaptations for heat exchange in different species of fox and finally how metabolic rate is influenced by the size of an organism and its ability to exchange heat with the surroundings. Key words: Surface area, volume, ratio, exchange, cube, heat, gas, metabolism, fox, ears

A resource suitable for use with both GCSE and A-Level students as a lesson starter, this worksheet provides an account of aseptic technique from an instruction manual; after each step in the instructions, students are required to comment on the reasons why each technique or precaution is necessary. A useful exercise to use at the beginning or an investigation involving microbiology. Key words: aseptic, bacteria, agar, contamination

A comprehensive four-page worksheet that deals with the physiology and function of the liver. This resource is aimed at advanced biology students and begins with a synoptic starter task that examines how blood flows through major body organs and the overall role of the liver in the mammalian circulatory system. The worksheet then moves on to look at gross anatomy of the liver and microscopic histology of the liver, covering details of the the liver lobules, bile canaliculi, sinusoids, hepatocytes and Kupffer cells.

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 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.

An activity aimed at either 7-10 year olds (simply do the activity described on the first two pages and ask students to describe their observations) or 11-14 year old students(ask students to complete the worksheet of questions on diffusion), this resource provides a really engaging way of of showing students the phenomenon of diffusion in a quick, simple, creative and edible way! Students are tasked with creating a simple picture or image on a plate using vegetable oil and a drinking straw. Skittle sweets/candy are then added to each area of the image and water is added. The colours from the skittle sweets/candy will start to diffuse and spread across the plate, colouring the image in. The colours are prevented from running into each other by the lines of oil. The activity provides a great way of discussing key questions such as why the colours are spreading, why are some colours spreading faster than others, what effect different temperature water has on the rate of spread of the colour and why oil stops the colours from spreading any further. Most importantly though, the investigation is a FUN science activity tailored to Christmas! The resource includes: Instruction sheet with diagrams, question worksheet for 11-14 year olds and various templates designs for Christmas pictures Key words: diffusion, colour, art, christmas, santa, holly, reindeer, fun, skittles, spread, investigation

A worksheet aimed at advanced level biology students, this resource is useful as a review of how colorimeters work and how they should be operated. The second worksheet contains a list of questions on different types of error that may result from laboratory investigations, some of which may be experienced when using a colorimeter: zero errors, systematic errors and random errors. The third worksheet is a differentiated version of the above, with an emphasis towards more simple ideas on the difference between qualitative and quantitative errors and calibration curves.

Worksheet starter task to recap the basics of amino acid structure

This resource is aimed at A-Level Biology students and lists the mechanisms behind each of four different lung diseases and disorders: asthma, tuberculosis, pulmonary fibrosis and emphysema. As well as being a useful collection of revision notes in itself, the task here is for students to explain how each of these diseases causes a reduced tolerance to exercise - this is often asked in exam questions and requires students to apply their knowledge of Fick's Law. Each disease will impact on surface area, concentration gradient and/or thickness of exchange surface thereby reducing the rate of diffusion; the challenge is for students to explain this