A Science teacher by trade, I've also been known to be found teaching Maths and PE! However, strange as it may seem, my real love is designing resources that can be used by other teachers to maximise the experience of the students. I am constantly thinking of new ways to engage a student with a topic and try to implement that in the design of the lessons.
A Science teacher by trade, I've also been known to be found teaching Maths and PE! However, strange as it may seem, my real love is designing resources that can be used by other teachers to maximise the experience of the students. I am constantly thinking of new ways to engage a student with a topic and try to implement that in the design of the lessons.
This lesson explains how negative feedback control maintains systems within narrow limits and uses biological examples to describe the meaning of positive feedback. The PowerPoint and accompanying resources have been designed to cover points 7.11 (i) and (ii) of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification but have been planned to provide important details for upcoming topics such as the importance of homeostasis during exercise and the depolarisation of a neurone.
The normal ranges for blood glucose concentration, blood pH and body temperature are introduced at the start of the lesson to allow students to recognise that these aspects have to be maintained within narrow limits. A series of exam-style questions then challenge their recall of knowledge from topics 1 - 6 as well as earlier in topic 7 to explain why it’s important that each of these aspects is maintained within these limits. The students were introduced to homeostasis at GCSE, so this process is revisited and discussed, so that students are prepared for an upcoming lesson on exercise, as well as for the next part of the lesson on negative feedback control. Students will learn how this form of control reverses the original change and biological examples are used to emphasise the importance of this system for restoring levels to the limits (and the optimum). The remainder of the lesson explains how positive feedback differs from negative feedback as it increases the original change and the role of oxytocin in birth and the movement of sodium ions into a neurone are used to exemplify the action of this control system.
This lesson describes and explains how temperature affects enzyme activity. The PowerPoint and the accompanying resource are part of the 1st lesson in a series of 3 which cover the content detailed in point 1.5 (iv) of the Edexcel A-level Biology B specification and this lesson has been specifically planned to tie in with the previous lesson covering 1.5 (i, ii & iii) where the structure, properties and mechanism of action of enzymes were introduced.
The lesson begins by challenging the students to recognise optimum as a key term from its 6 synonyms that are shown on the board. Time is taken to ensure that the students understand that the optimum temperature is the temperature at which the most enzyme-product complexes are produced per second and therefore the temperature at which the rate of an enzyme-controlled reaction works at its maximum. The optimum temperatures of DNA polymerase in humans and in a thermophilic bacteria and RUBISCO in a tomato plant are used to demonstrate how different enzymes have different optimum temperatures and the roles of the latter two in the PCR and photosynthesis are briefly described to prepare students for these lessons in topics 7 and 5.
Moving forwards, the rest of the lesson focuses on enzyme activity at temperatures below the optimum and at temperatures above the optimum. Students will understand that increasing the temperature increases the kinetic energy of the enzyme and substrate molecules, and this increases the likelihood of successful collisions and the production of enzyme-substrate and enzyme-product complexes. When considering the effect of increasing the temperature above the optimum, continual references are made to the previous lesson and the control of the shape of the active site by the tertiary structure. Students will be able to describe how the hydrogen and ionic bonds in the tertiary structure are broken by the vibrations associated with higher temperatures and are challenged to complete the graph to show how the rate of reaction decreases to 0 when the enzyme has denatured.
Please note that this lesson has been designed specifically to explain the relationship between the change in temperature and the rate of enzyme activity in a reaction and not the practical skills that would be covered in a core practical lesson
This lesson introduces the differences between ectotherms and endotherms and then describes the behavioural responses of an ecotherm. The PowerPoint and accompanying resource have been designed to cover specification point 9.9 (vi) of the Edexcel A-level Biology B specification which states that students should understand how ectotherms rely on the external environment for their temperature control. The main aim when designing the lesson was to support students in making sensible and accurate decisions when challenged to explain why these types of organisms have chosen to carry out a particular response. A wide range of animals are used so students are engaged in the content matter and are prepared for the unfamiliar situations that they will encounter in the terminal exam. Time is also taken to compare ectotherms against endotherms so that students can recognise the advantages and disadvantages of ectothermy when covered in the following lesson.
This fully-resourced lesson covers the meaning of the 9 genetic terms that are detailed in point 2.13 (i) of the Pearson Edexcel A-level Biology (Salters Nuffield) specification as well as four other key terms which will need to be used later in topic 2, 3 and 8.
In the following lessons, students are expected to be able to demonstrate and apply their knowledge and understanding of genetic diagrams and phenotypic ratios to show patterns of inheritance and this is only possible with a clear understanding of the genetic terminology that will be used in related exam questions. As some of these terms were met at GCSE, this lesson has been designed to build on this prior knowledge and provide clear explanations as to their meanings as well as numerous examples of their use in both questions and exemplary answers. The main task provides the students with an opportunity to apply their understanding by recognising a dominance hierarchy in a multiple alleles characteristic and then calculating a phenotypic ratio when given a completed genetic diagram. Other tasks include prior knowledge checks, discussion points to encourage students to consider the implementation of the genetic terms and quiz competitions to introduce new terms, maintain engagement and act as an understanding check.
The 13 terms are genome, gene, chromosome, gene locus, homologous chromosomes, alleles, dominant, recessive, genotype, phenotype, homozygotes and heterozygotes
This lesson focuses on the nature of the genetic code and specifically focuses on the degenerate nature to make a link to gene mutations which is covered later in topic 2. The PowerPoint has been designed to cover point 2.7 of the Pearson Edexcel A-level Biology (Salters Nuffield) specification which states that students should understand how the descriptive terms triplet code, degenerate and non-overlapping relate to the genetic code.
The lesson begins by introducing the terms near universal and non-overlapping in addition to degenerate. A quick quiz competition is used to generate the number 20 so that the students can learn that there are 20 proteinogenic amino acids in the genetic code. This leads into a challenge, where they have to use their prior knowledge of DNA to calculate the number of different DNA triplets (64) and the mismatch in number is then discussed and related back to the lesson topic. Moving forwards, substitutions and deletions are briefly introduced so that they can see how although one substitution can change the primary structure, another will change the codon but not the encoded amino acid. The lesson concludes with a brief look at the non-overlapping nature of the code so that the impact of a base deletion can be understood when covered in greater detail with cystic fibrosis
This concise lesson describes the basic structure of an amino acid and introduces them as the monomers of polypeptides. The engaging PowerPoint has been designed to cover point 2.9 (i) of the Pearson Edexcel A-level Biology A specification and has been specifically written to lead into the next lesson on dipeptides and polypeptides.
The lesson begins with a prior knowledge check, where the students have to use the 1st letters of 4 answers to uncover a key term. This 4-letter key term is gene and the lesson begins with this word because it is important for students to understand that these sequences of bases on DNA determine the specific sequence of amino acids in a polypeptide as detailed in specification point 2.8. Moving forwards, the students are given discussion time to work out that there are 64 different DNA triplets and will learn that these encode for the 20 amino acids that are common to all organisms. The main task of the lesson is an observational one, where students are given time to study the displayed formula of 4 amino acids. They are not allowed to draw anything during this time but will be challenged with 3 multiple choice questions at the end. This task has been designed to allow the students to visualise how the 20 amino acids share common features in an amine and an acid group. A quick quiz round introduces the R group and time is taken to explain how the structure of this side chain is the only structural difference, before cysteine is considered in greater detail due to the presence of sulfur atoms. Students are briefly introduced to disulfide bridges so they will recognise how particular bonds form between the R groups in the tertiary structure which is covered in the next lesson. The lesson concludes with one more quiz round called LINK TO THE FUTURE where the students will see the roles played by amino acids in the later part of the course such as translation and dipeptides.
This fully-resourced lesson describes how triglycerides are formed during condensation reactions and compares saturated and unsaturated lipids. The engaging PowerPoint and accompanying worksheets have been designed to cover the points 1.14 (i) & (ii) of the Pearson Edexcel A-level Biology A specification and links are also made to related future topics such as the importance of the myelin sheath for the conduction of an electrical impulse.
The lesson begins with a focus on the basic structure and roles of lipids, including the elements that are found in this biological molecule and some of the places in living organisms where they are found. Moving forwards, the students are challenged to recall the structure of the carbohydrates from topics 1.12 & 1.13 so that the structure of a triglyceride can be introduced. Students will learn that this macromolecule is formed from one glycerol molecule and three fatty acids and have to use their understanding of condensation reactions to draw the final structure. Time is taken to look at the difference in structure and properties of saturated and unsaturated fatty acids and students will be able to identify one from the other when presented with a molecular formula. The final part of the lesson explores how the various properties of a triglyceride mean that it has numerous roles in organisms including that of an energy store and source and as an insulator of heat and electricity.
This fully-resourced lesson describes the relationship between the molecular structure of a triglyceride and its functions in living organisms. The engaging PowerPoint and accompanying worksheets have been designed to cover specification point 2.2 (f) of the CIE International A-level Biology course and links are also made to related future topics such as the importance of the myelin sheath for the conduction of an electrical impulse and the use of lipids as a respiratory substrate.
The lesson begins with a focus on the basic structure and roles of lipids, including the elements that are found in this biological molecule and some of the places in living organisms where they are found. Moving forwards, the students are challenged to recall the structure of the carbohydrates from earlier in topic 2 so that the structure of a triglyceride can be introduced. Students will learn that this macromolecule is formed from one glycerol molecule and three fatty acids and have to use their understanding of condensation reactions to draw the final structure. Time is taken to look at the difference in structure and properties of saturated and unsaturated fatty acids and students will be able to identify one from the other when presented with a molecular formula. The final part of the lesson explores how the various properties of a triglyceride mean that it has numerous roles in organisms including that of an energy store and source and as an insulator of heat and electricity.
Simple and facilitated diffusion are forms of passive transport and this lesson describes the factors that increase the rate of this movement across membranes. This fully-resourced lesson is the first in a series of two that have been designed to cover specification point 2.4 of the Pearson Edexcel A-level Biology A and the involvement of channel and carrier proteins is also described and discussed.
In a number of previous lessons that covered specification points 2.1 and 2.2, students were provided with the details of gas exchange surfaces and the structure and properties of cell membranes. This lesson continually refers back to the content of these lessons so that links can be made between the movement across a cell membrane with the concentration gradient, the parts of the membrane involved and any features that may increase the rate at which the molecules move. A series of questions about the alveoli is used to demonstrate how a large surface area, a short diffusion distance and the maintenance of a steep concentration gradient will increase the rate of simple diffusion. One of two quick quiz rounds is then used to introduce temperature and size of molecule as two further factors that can affect simple diffusion. The remainder of the lesson focuses on facilitated diffusion and describes how transmembrane proteins are needed to move small, polar or large molecules from a high concentration to a lower concentration across a partially permeable membrane.
The other lesson included in this series to cover specification point 2.4 describes active transport, endocytosis and exocytosis.
This engaging lesson describes how chromosome mutations result in changes to the number or structure of chromosomes and focuses on Downs and Turner’s syndrome. The PowerPoint and accompanying resources have been designed to cover specification points 2.3 (vi) and (vii) as detailed in the Edexcel A-level Biology B specification.
A human karyotype which has not been altered by a mutation is studied at the start of the lesson to allow students to recall the usual number of chromosomes as well as the sex chromosomes. They are then challenged to identify the differences when presented with the karyotypes of sufferers of Downs, Turner’s and Klinefelter’s syndrome. Students will learn that in the majority of cases, these conditions are the result of non-disjunction and having been assisted in the explanation of the outcome for Downs and Klinefelters, they have to form their own for Turner’s. The remainder of the lesson looks at other types of mutations, including translocation, and students will also see how whole sets of chromosomes can be duplicated in polyploidy.
This lesson describes how maltose, sucrose and lactose are synthesised during condensation reactions and broken down during hydrolysis reactions. The PowerPoint and accompanying question sheet have been designed to cover point 1.1 (iii) of the Edexcel A-level Biology B specification but also make links to the previous lesson on monosaccharides when considering the different components of these three disaccharides.
The first section of the lesson focuses on a prefix and a suffix so that the students can recognise that the names of the common disaccharides end in -ose. In line with this, a quick quiz round is used to introduce maltose, sucrose and lactose before students are challenged on their prior knowledge as they have to describe how condensation reactions and the formation of glycosidic bonds were involved in the synthesis of each one. The main task of the lesson again challenges the students to recall details of a previous lesson as they have to identify the monomers of each disaccharide when presented with the displayed formula. Time is taken to show how their knowledge of these simple sugars will be important in later topics such as enzymes, translocation in the phloem and the lac operon in the control of gene expression. The lesson finishes with two exam-style questions where students have to demonstrate and apply their newly acquired knowledge
This revision resource contains a concise yet informative PowerPoint (25 slides) and a worksheet that will enable the students to assess their understanding of the topic B4 (Enzymes) content of the CIE IGCSE Combined Science specification for examination in June and November 2020 and 2021. The range of exam questions (with explained answers), quick tasks and quiz competitions have been designed to cover as much content as possible but the following topics have received particular attention:
Enzymes as biological catalysts that speed up reactions
The binding of a substrate with the active site of an enzyme
The effect of a changing pH on the activity of an enzyme
The effect of a changing temperature on the activity of an enzyme
Denaturation
This concise, engaging revision lesson has been designed to include activities that will motivate the students whilst they assess their understanding of topic B3 (Biological molecules) of the CIE IGCSE Combined Science specification. An understanding of biological molecules is fundamental to the understanding of a lot other Biology topics and this lesson has attempted to make the links between the different areas.
The range of activities which include exam questions, quick tasks and quiz competitions have been written to cover as much of the content as possible but the following topics have received particular attention:
The chemical elements in carbohydrates
The formation of starch and glycogen from glucose
The iodine test for starch
Lipids are formed of fatty acids and glycerol
Investigational skills
The ethanol emulsion test for lipids
This resource includes a PowerPoint (27 slides) and a worksheet with a task about the digestion of milk fat so students can recognise the components of lipids
This engaging lesson acts as an introduction to carbohydrates and describes the differences between monosaccharides, disaccharides and polysaccharides. The PowerPoint and accompanying worksheet have been designed to cover the first part of points 1.12 & 1.13 of the Pearson Edexcel A-level Biology A specification and make clear links to the upcoming lessons in this sub-topic on these three main groups of carbohydrates.
The lesson begins with a made-up round of the quiz show POINTLESS, where students have to try to identify four answers to do with carbohydrates. In doing so, they will learn or recall that these molecules are made from carbon, hydrogen and oxygen, that they are a source of energy which can sometimes be rightly or wrongly associated with obesity and that the names of the three main groups is derived from the Greek word sakkharon. A number of quick quiz rounds have been written into the lesson to introduce key terms in a fun and memorable way and the first round allows the students to meet some of common monosaccharides. Moving forwards, students will learn that a disaccharide is formed when two of these monomers are joined together and they are then challenged on their knowledge of condensation reactions which were originally encountered during the lesson on water. Students will understand how multiple reactions and multiple glycosidic bonds will result in the formation of a polysaccharide and glycogen and starch are introduced as well as amylose and amylopectin as components of this latter polymer. The final part of the lesson considers how hydrolysis reactions allow polysaccharides and disaccharides to be broken back down into monosaccharides.
This lesson reminds students of the meaning of homeostasis and describes the how thermoregulation maintains the body in dynamic equilibrium during exercise. The PowerPoint has been designed to cover point 7.17 of the Edexcel International A-level Biology specification.
Students were introduced to homeostasis at GCSE and this lesson has been written to build on that knowledge and to add the key detail needed at this level. Focusing on the three main parts of a homeostatic control system, the students will learn about the role of the internal and peripheral thermoreceptors, the thermoregulatory centre in the hypothalamus and the range of effectors which bring about the responses to restore optimum levels.
The following responses are covered in this lesson:
Vasodilation
Increased sweating
Body hairs
In each case, time is taken to challenge students on their ability to make links to related topics such as the arterioles involved in the redistribution of blood and the high specific latent heat of vaporisation of water.
This lesson describes the process of gas exchange between air in the alveoli and the blood. The PowerPoint and accompanying worksheet have been designed to cover point 9.1 (d) of the CIE A-level Biology specification
Gas exchange at the alveoli is a topic that was covered at GCSE so this lesson has been written to challenge the recall of that knowledge and to build on it.
The main focus of the lesson is the type of epithelium found lining the alveoli and students will discover that a single layer of flattened cells known as simple, squamous epithelium acts to reduce the diffusion distance.
The following features of the alveolar epithelium are also covered:
Surface area
Moist lining
Production of surfactant
The maintenance of a steep concentration gradient
As a constant ventilation supply is critical for the maintenance of the steep concentration gradient, the final part of the lesson considers the mechanism of ventilation
This lesson describes the inheritance of two non-interacting unlinked genes and guides students through the calculation of phenotypic ratios. The PowerPoint and the accompanying question sheet (which is differentiated) have been designed to cover point 8.2 (iii) of the Edexcel A-level Biology B specification.
As the previous lesson described the construction of genetic crosses and pedigree diagrams, students are aware of the methods involved in writing genotypes and gametes for the inheritance of a single gene. Therefore, the start of this lesson builds on this understanding to ensure that students recognise that genotypes contain 4 alleles and gametes contain 2 alleles when two genes are inherited. The students are taken through the steps of a worked example to demonstrate the key steps in the calculation of a phenotypic ratio before 2 exam-style questions challenge them to apply their newly-acquired knowledge. Mark schemes are displayed within the PowerPoint to allow students to assess their progress. The phenotypic ratio generated as the answer to the final question is 9:3:3:1 and time is taken to explain that this is the expected ratio when two heterozygotes for two genes are crossed which they may be expected to use when meeting the chi squared test in an upcoming lesson
This lesson describes the effect that treaties such as CITES have had on global diversity. The PowerPoint and accompanying worksheets have been primarily designed to cover point 10.4 (ii) of the Edexcel A-level Biology B specification but has been planned to constantly challenge them on their knowledge of topic 3.3 (biodiversity) as a local conservation agreement is also considered
Many hours of research have gone into the planning of this lesson to ensure that a range of interesting biological examples are included, with the aim of fully engaging the students in the material to increase its relevance. The students will learn that the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) was first agreed in 1973 and that 35000 species are currently found in appendix I, II or III. Time is taken to go through the meaning of each appendix and then the following animal and plant species are used to explain the finer details of the agreement:
Tree pangolin, eastern black rhino for CITES appendix I
Darwin’s orchid for CITES appendix II
Four-horned antelope for CITES appendix III
Exam-style questions are used to check on their understanding of the current topic as well as to challenge their knowledge of previously-covered topics such as the functions of keratin, when considering the structure of the rhino horn. Each of these questions has its own markscheme which is embedded in the PowerPoint and this allows the students to constantly assess their progress.
The final part of the lesson considers the Countryside Stewardship Scheme as a local conservation agreements and discusses the reasons behind some of the key points. Students are told that farmers, woodland owners, foresters and land managers can apply for funding for a range of options including hedgerow management, low input grassland, buffer strips, management plans and soil protection options. The importance of the hedgerows for multiple species is discussed, and again a real-life example is used with bats to increase the likelihood of retention. The last task challenges them to use their overall knowledge of biodiversity to explain why buffer strips consisting of multiple types of vegetation are used and to explain why these could help when a farmer is using continuous monoculture.
This lesson describes a range of methods that can be used to assess the distribution and abundance of organisms in a local area. The PowerPoint and accompanying worksheets have been designed to cover points [c] and [d] of topic 18.1 of the CIE A-level Biology specification and describe the use of frame quadrats, line and belt transects, and the mark-release-recapture method.
Due to the substantial mathematical content of the A-level Biology exams, as well as descriptions of the different methods, there is a focus on the range of calculations that are used to estimate the population of either sessile or motile species. As shown by the image, step by step guides are used to walk the students through the key stages in these calculations before exam-style questions challenge them to apply their understanding and mark schemes are included in the lesson to allow them to immediately assess their progress. The precautions and assumptions associated with the mark-release-recapture method are discussed and links are made to stabilising selection as covered in topic 17 when considering how the number of species have changed over time.