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 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

Worksheet that asks students to work through a chi-squared analysis of data from an investigation into PTU tasting ability. Useful as a lesson starter or plenary review on chi-sqaured. Keywords: chi-squared, statistics, PTU, tasting, null hypothesis, probability, degrees of freedom, critical value

A worksheet resource that could be used by either 14-16 or 16-18 year old biology students, this resource provides an 'active video' task on the history of thalidomide with a series of question prompts that students complete while watching the video clip. the video clip can be found here: https://www.youtube.com/watch?v=p0QpnqjKGJo The video clip provides an overview of the thalidomide tragedy and how the United States stood their ground in refusing a drug licence while the disaster played out across the rest of the world. This is a good activity to set the scene for any topic on how drugs are developed and the importance of drug testing and clinical trials. Key words: Thalidomide, disaster, focomelia, drugs, clinical trials, pharmaceutical, USA, regulations

A worksheet aimed at advanced biology students, this resource provides several prompts for students to research and learn about the nature of the nerve impulse and action potential. Extension tasks are also provided along with weblinks to animations and information sources. This is a good activity to set a class as a homework or as an independent learning task prior to teaching of the topic in class. Key words: Nerve, neurone, nerve impulse, action potential, depolarisation, repolarisation, refractory period, resting potential, propagation, sodium, potassium, influx, efflux, membrane

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 worksheet aimed at advanced biology students, this resource provides prompts and questions to guide student research into co-ordination and homeostasis of the human body. The worksheet consists of questions relating to the role, nature and mechanisms of hormones, local chemical mediators and the nervous system. Key words: nervous system, hormones, homeostasis, chemical mediator, receptor, signal, communication, impulse, co-ordination

A worksheet aimed at advanced biology students, this resource provides a series of exercises that help students understand the nature of the genetic code and the impact of mutations. Students are required to decode a piece of DNA using the decode table provided, before then considering how a substitution, deletion or addition could change how the sequence is decoded. This is an excellent resource for driving home the point about frameshift mutations and how some mutations may be silent.

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 worksheet aimed at advanced level biology students, this resource provides a list of key statements and key words related to the topic of mitosis. The worksheet can be used as a revision activity whereby students draw out cell diagrams depicting each stage of mitosis and then use the key words and statements to annotate their diagrams appropriately. Key words: key words, key statements, mitosis, centrioles, prophase, metaphase, anaphase, telophase, cytokinesis, interphase, chromosomes, nucleus, spindle fibres

A worksheet aimed at advanced level biology students which introduces the concept of nervous and hormonal control of the body. The worksheet consists of some introductory questions that require students to consider the nature, mechanisms, speed and duration of hormonal communication versus nervous communication. Key words: communication, hormone, nerve, impulse, endocrine, neurotransmitter, chemical messenger

A worksheet aimed at advanced biology students, this is ideal as a starter or plenary task following a topic on glucose homeostasis. The worksheet consists of eighteen questions related to glucose homeostasis (a 'what am I?' quiz) which require single word answers. All answers are provided on the second page of the worksheet. A good activity to consolidate key word vocabulary from this topic. Key words: glucose, glycogen, homeostasis, starch, gluconeogenesis, glycogenolysis, liver, pancreas, islets of langerhans, alpha cells, beta cells

A worksheet aimed at either higher ability 14-16 students or advanced biology students, this resource is useful as a starter or plenary exercise to recap ideas on homeostasis and the mechanisms by which heat can be gained or lost (various scenarios are given for students to explain). The worksheet concludes with some research tasks on the physiological mechanisms of thermoregulation. Key words: homeostasis, thermoregulation, temperature, conduction, convection, radiation, heat gain, heat loss

A worksheet aimed at advanced biology students, this comprehensive set of worksheets can effectively be used to introduce the concept of homeostasis (focusing on negative feedback mechanisms and the need to keep a steady state) and thermoregulation. Students can work their way through each section of the worksheet before a class discussion to check understanding - for some sections a teacher may decide to lead on an explanation before using the worksheet exercises as a way of checking understanding. Key words: homeostasis, negative feedback, thermoregulation, sweating, vasoconstriction, vasodilation, piloerection, shivering

A worksheet aimed at advanced biology students which concisely deals with the causes and mechanisms of hypothermia and hyperthermia. The worksheet concludes by looking at how endotherms and ectotherms regulate body temperature. Both sections of the worksheet include questions that help students to build their understanding withe reference to graphical displays of core temperature for each scenario. Key words: temperature, hypothermia, hyperthermia, endotherm, ectotherm

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 advanced biology students, this resource is useful as a starter exercise on the topic of gas exchange in fish. The worksheet includes a mix and match task that focuses on the basic anatomical features associated with gills followed by questions related to the single circuit layout of a fish's circulatory system. Key words: fish, circulatory, counter-current, concurrent, blood, gas exchange, oxygen, carbon dioxide, gills, Fick's law, equilibrium, surface area, concentration gradient, exchange surface

A worksheet aimed at advanced biology students, this resource is suitable as a lesson starter for a topic on gas exchange in fish. The worksheet requires students to consider the difference in circulatory system layout between a fish and a mammal before focusing on the differences between concurrent and counter-current exchange. Key words: fish, circulatory, counter-current, concurrent, blood, gas exchange, oxygen, carbon dioxide, gills, Fick's law, equilibrium, surface area, concentration gradient, exchange surface

A worksheet aimed at advanced biology students, this resource provides a series of questions to recap basic understanding (e.g. sequence the physiological events that occur during thermoregulation) followed by more developmental questions to challenge students and get them thinking more deeply about the topic and various contexts where it could be applied. Key words: thermoregulation, temperature, heat, heat loss, heat gain, sweating, shivering, vasoconstriction, vasodilation