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IB style topic testsfree27 December 2014

These test are designed to help teachers assess students at the end of each topic and to help students practise IB style questions. They have been written specially for Inthinking Biology by experienced... more

Topic 1 - Cells revision activitiesfree29 November 2016

All the different aspects of the cells topic on a single A3 sheet, for revision. By completing short questions or explanations students are forced to review the whole topic and complete an overview of... more

Ecological terms.25 March 2019

"Ecology is the study of the distribution and abundance of organisms, the interaction between organisms, the interaction between organisms and their environment, and structure and function of ecosystems."... more

Classification of Plants3 November 2017

Starting with some self study activities students begin to learn the names and features of the four plant phyla required for IB. Then, using a dichotomous key students search for examples of each phyla... more

Paper 3 Section A - questionsfree16 April 2016

Paper 3 section A is a new part of the IB Biology examinations this year in 2016The following details are adapted from Inthinking Chemistry pages by Geoff Neuss and information from the IBO more

Genetically Modified Organisms.21 March 2018

In an excellent BBC interview with some anti-GMO protesters destroying a field of research crops some young people were asked to explain why they were taking this action. None of those interviewed could... more

Theoretical Genetics 1.2 February 2018

In this lesson students will be shown the link between chromosomes and genetics. A powerpoint intro to allele and genotypes in a simple case of inheritance of flower colour illustrates the link and demonstrates... more

Annotating IA Investigationsfree10 April 2019

Once students have finished their Individual Investigation that's it! They won't complete another assessed experiment during their IB and this makes me consider the way I annotate the investigations while... more

Topic 10 - Genetics HL Revision activities26 June 2017

If you want to see the all the different aspects of this topic on a single A4 sheet this page will help you. By completing short questions or cloze activities students are forced to review the whole topic... more

Evolution examples8 October 2017

Students investigate adaptive radiation and industrial melanism as well as gradual divergence of populations into separate species. All of these ideas have been contested by some groups so IB students... more

Variation & overproduction7 September 2015

To understand how natural selection leads to evolution it is important to know about variation and overproduction of offspring. These two concepts are the key to understanding evolution. In this activity... more

Chromosomesfree21 January 2018

This lesson begins with a comparison of prokaryote and eukaryote chromosomes and an introduction to the concept of diploid and haploid nuclei. The second activity introduces the use of databases to compare... more

Ventilation & lung disease22 July 2015

Students begin by looking at the muscle contractions which cause the pressure changes inside the thorax that force air in and out of the lungs to ventilate them. This is followed by an experiment to monitor... more

Classification & binomial names20 July 2015

Students will learn how to classify organisms according to their taxonomic group, and how to understand the binomial nomenclature. These are a few introductory slides and then a card sorting activity... more

Topic 11 - Physiology HL Revision activities14 December 2015

If you want to see the all the different aspects of this topic on a single A4 sheet this page will help you. By completing short questions or cloze activities students are forced to review the whole topic... more

Transcription - extras for HL8 January 2019

This lesson begins with a review of the process of transcription and the role of RNA polymerase but quickly turns to the control of gene expression using nucleosomes and methylation. Experiments with... more

Photosynthesis Theory23 February 2016

Standard level students need to know about photolysis and the light independent reactions which take place in the stroma but with only simple details. This activity leaves out the complexity and gives... more

Blood clotting and heart disease.1 July 2018

Students sequence and explain the events of the chemical cascade which leads to the formation of a blood clot or scab using SOLO hexagons. This is followed by a short activity outlining an important application... more

Alveoli & gas exchange3 February 2019

Students learn about the structure of the lungs and their alveoli including type I and II pneumocytes. After a short quiz on basic lung structure a short screen cast helps students to complete a diagram... more

Nerve impulses.28 September 2018

Name three different roles of integral proteins in cell membranes.How can integral proteins in a neurone plasma membrane cause an electrical potential across the membrane?What do these proteins do to... more

Intro to cladistics18 December 2016

What is a clade? How can we explain analogous and homologous traits using cladograms? What do we need to know about cladograms? All these important questions are covered in this lesson plan using a... more

Cell Respiration.21 January 2019

With the smell of caramel from the burning glucose filling the lab, students discuss the need for metabolic pathways in respiration. A card sort activity and discussion will outline the main ideas for... more

Meristems and Growth.29 January 2018

What is a meristem and how is it that a plant can keep growing for the whole of its life? Micropropagation using the plant meristems as a source of undifferentiated cells has become an important method... more

Theoretical Genetics 2.9 February 2018

Beginning with a review of the punnet square questions from last lesson, students are then introduced to some more complex genetics using the example of human blood groups. Teacher led Description of... more

Intestine Structure & Function.30 May 2017

After learning to draw an annotated diagram of the digestive system students extend their understanding by looking at details of intestine structure and how they relate to function. This includes identification... more

Photosynthetic pigments 27 January 2017

Students investigate a simple practical method of separating photosynthetic pigments (practical 4)using paper chromatography (or thin layer chromatography). Following this there is an animation of chromatography... more

Structure of the digestive system.16 November 2016

With a short screencast students learn a simple method of drawing a diagram of the digestive system. Annotations are added and students can practice their knowledge using some printable flashcards or... more

Describing trends in IB graphsfree2 June 2015

Describing the data on a graph is a skill in Biology. Achieving the marks in an IB exam is more difficult that it looks. Students must do exactly what the question asks and give precise details in their... more

Topic 9 - Plant biology HL revision activities14 October 2018

If you want to see the all the different aspects of this topic on a single A4 sheet this page will help you. By completing short questions or cloze activities students are forced to review the whole topic... more

Light Dependent Reactions14 March 2019

This activity reviews the light dependent reactions of photosynthesis which occurs on the thylakoids of the chloroplast. A first activity introduces the parts of the membrane and the stages of the reactions,... more

Option C - Ecology revision activities31 January 2019

This page contains some suggestions for revision. To see the big picture, an overview of the whole option, the A3 revision sheets on this page will help. There are two revision sheets, one for the SL... more

Ecology mini-investigation11 October 2018

What does an Individual investigation look like? Students will try out all the steps of the planning and carrying out of the individual investigation in the collaborative safety of group work. For each... more

Light Independent Reactions5 April 2019

The reactions of the Stroma of the Chloroplast are known as the light independent reactions and also the Calvin cycle. This activity introduces some of the molecules to students and some steps of the... more

Gene pools26 May 2017

After consideration of what a gene pool is and the way that evolution causes changes in gene pools this lesson looks at the driving forces of speciation using the examples of Bird of paradise species... more

IA investigation - teacher's marking activity15 November 2015

For most teachers one of the main worries when marking the new IA investigations is, "Am I interpreting the IA marking criteria correctly?" To help us all to mark a little more confidently here is an... more

Kidney and nephrons.21 May 2017

What happens inside the kidney?How can the kidney filter some molecules, like urea, out of the blood?Draw a diagram of the kidney using this screen cast as a guide. Remember to keep the lines nice and... more

Sex Linked Genes.4 March 2018

In this lesson plan students read about the inheritance of colour blindness and hemophilia as examples of sex linkage. Then they make structured notes on the essential points using the structured notes... more

Leaf stomata & transpiration7 January 2016

A short video introduction to the roles of cells in a leaf followed by some simple note taking about leaf structure and function. The function of stomata is linked to carbon dioxide absorption and also... more

Classification gamesfree11 August 2017

Learning the key features of the animal and plant phyla requires some repetition and is not really much fun. So this activity tries to change that. Using a simple set of cards students learn the names... more

Antigens and antibodies 19 February 2015

How can the proteins on the surface of cells, called antigens, help the body's immune system to identify pathogens?Use the following slides to introduce antigens and antibodies Antigens & antibodies more

Muscle structure & function.6 October 2016

Students use a short powerpoint introduction to identify key points of muscle structure and the interaction between myosin and actin filaments in sarcomeres before answering some questions on a worksheet.... more

Hormones introduction4 December 2017

Students are introduced to hormones in this lesson using three examples, leptin, thyroxin and melatonin. These examples clearly illustrate the nature of hormones and ideas about homeostasis. After some... more

Controlling Heartbeatfree21 January 2016

This simple classroom activity is worksheet based with an interactive whiteboard presentation. It will help students to make sense of the links between the medulla oblongata, the adrenal glands and the... more

Electron Transport Chain.14 February 2019

Modelling the biochemical pathway of the electrontransport chain is learned through the activities in this lesson. Using some simple slides students are introduced to the movement of H+ ions and electrons... more

Topic 10 - Genetics HL revision list17 December 2015

This pages gives outline details of the content of the topic together with essential questions and student skills and applications. Helpful for revision.Crossing overEssential Questions more

Immune System 22 December 2014

This lesson contains two constructivist activities. In the first students research and classify microorganisms into pathogens and non pathogens. The second activity is a challenge to narrate a series... more

Transcription of mRNA from DNA18 January 2019

Using an animated visualisation of RNA polymerase students will learn how to describe the process of translation in simple terms. In order to do this a good knowledge of the structure of RNA is important.... more

Reclassification of figworts using cladisticsfree13 October 2016

In this lesson students first try to make a cladogram using the physical appearance of flowers from the figwort family. This illustrates how classification has been done for many years. In the second... more

DNA Replicationfree17 March 2019

The central dogma of molecular biology, described by Francis Crick, begins with DNA replication. It really is the essence of inheritance and perhaps even the essence of life itself. At SL there are just... more

Polygenic Inheritance.20 June 2016

Using a powerpoint introduction students learn about another example of inheritance which Mendel didn't attempt to explain. Polygenic inheritance is probably the most common type of inheritance but even... more