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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

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

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

Photosynthesis Experimentsfree16 February 2019

This activity introduces a simple method of measuring the rate of photosynthesis and leads students to design their own investigation of a factor which affects it. A second activity illustrates how the... 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

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

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

DNA Replicationfree1 June 2017

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

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

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

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

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

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

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

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

Hormones and the menstrual cycle3 December 2017

Students are introduced to the functions of the hormones of the menstrual cycle with the aid of a short presentation. This is followed by an activity looking at the effects of hormones on one another... more

DNA structure - Extras for HL9 January 2019

This lesson introduces students to nucleosomes, and some of the details of DNA structure which will help to understand DNA replication. This includes the purine and pyrimidines bases as well as 5' and... 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

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

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

HL Respiration introduction2 November 2015

Students are introduced to four important reaction types found in respiration, oxidation, reduction, phosphorylation and decarboxylation. There is a short presentation which helps to explain each reaction... 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

Activation energy and enzyme pathwaysfree17 February 2019

Students are introduced to a simple metabolic pathway consisting of a chain of enzyme-catalysed reactions leading to the Kreb's cycle which is a cycle of enzyme catalysed reactions. The method of enzymes... 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

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

Osmoregulation.21 October 2015

Students learn about three methods of controlling water balance in this lesson. A short presentation reminds students about osmosis and introduces some examples osmoconformers and osmoregulators from... 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

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

Harvey and the search for ova11 November 2015

This lesson includes annotation of reproductive organ diagrams just as biologists, Aristotle, Harvey and de Graaf did in history in their quest to discover the function of the ovary and the existence... more

Light Dependent Reactions28 February 2016

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

Antibody production7 June 2018

Two important ideas about antibodies are addressed in this lesson plan. Students first discuss ideas about immunity and mark a piece of student work using a mark scheme to consolidates their understanding... 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

Homeostasis of Glucose.9 November 2015

This lesson introduces the way insulin and glucagon control blood glucose levels. Students arrange SOLO hexagons to explain the homeostasis process and to build on their prior knowledge of insulin or... 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

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

Drawing biological molecules24 September 2018

Students learn how to draw the following molecules; glucose, ribose, saturated fatty acid and an amino acid. They answers questions which gives practice in recognition of each molecule activity. This... more

Yeast and Catalase Experiment17 November 2016

Following a teacher demonstration of measuring the rate of hydrogen peroxide and catalase enzyme students carry out a circus of three simple enzyme experiments.These experiments illustrate the effects... 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

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

Synapses.7 December 2018

This activity involves lots of discussion and a little competition to help students learn the details of synaptic transmission. First by annotation of simple diagrams showing the structures of a synapse... more

Vaccination18 November 2018

Measles is a highly contagious disease and one of the leading causes of death of children under 5. In 2013 it is estimated that almost 150 thousand children died from measles worldwide. The World Health... 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

Meiosis.8 November 2016

The remarkable breeding experiments carried out by Gregor Mendel between 1856 and 1863 are now considered to be the origins of modern genetics. It's easy to overlook the brilliance of Mendel's data analysis... more

Heart Dissection & Diagram2 December 2017

Using a short screen cast students learn a simple method of drawing a diagram of the heart. Annotations are added and students can practice their knowledge using some printable flashcards or a range of... 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

Respiration experiments.19 September 2015

Two nice experiments, the first looks a respiration rates in fly larvae and the second links the structures of different carbohydrates to the rate of respiration in yeast. This is an opportunity to discuss... 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

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

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

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