This fully-resourced lesson describes the ultrastructure of eukaryotic cells and the functions of the different cellular components. The engaging and detailed PowerPoint and accompanying resources have been designed to cover points 2.1.1 (g) & (i) of the OCR A-level Biology A specification and therefore also describes the interrelationship between the organelles involved in the production and secretion of proteins. As cells are the building blocks of living organisms, it makes sense that they would be heavily involved in all 6 modules in the OCR course and intricate planning has ensured that links to the lessons earlier in module 2.1.1 are made as well as to the upcoming modules. The lesson uses a wide range of activities, that include exam-style questions, class discussion points and quick quiz competitions, to maintain motivation and engagement whilst describing the relationship between the structure and function of the following organelles: nucleus nucleolus centrioles ribosomes rough endoplasmic reticulum Golgi apparatus lysosomes smooth endoplasmic reticulum mitochondria cell surface membrane vacuole chloroplasts plasmodesmata Details of the cilia and flagella are covered in the lesson on the importance of the cytoskeleton. All of the worksheets have been differentiated to support students of differing abilities whilst maintaining challenge Due to the detail that is included in this lesson, it is estimated that it will take in excess of 3 hours of allocated A-level teaching time to go through all of the tasks

This lesson describes how to use and manipulate the magnification formula to calculate the magnification or the actual size in a range of units. The PowerPoint and accompanying resources have been designed to cover point 2.1.1 (e) of the OCR A-level Biology A specification and contains a number of quiz rounds as part of the competition that runs throughout all of the module 2.1.1 lessons The students are likely to have met the magnification formula at GCSE so this lesson has been written to build on that knowledge and to support them with more difficult questions when they have to calculate actual size without directly being given the magnification. A step by step guide is used to walk the students through the methodology and useful tips are provided. Students could be asked to calculate the actual size in millimetres, micrometres, nanometres or picometres so time is taken to ensure that they can convert between one and another.

This fully-resourced lesson describes how light and electron microscopy can be used to observe cells and cell structures. The engaging PowerPoint and accompanying resources have been designed to cover the content of points 2.1.1 (a) & (f) of the OCR A-level Biology A specification and also describes the difference between magnification and resolution As this is likely to be one of the very first lessons that students cover in their A-level studies, it’s important to maintain motivation from the off whilst covering the detailed and important content of microscope studies. In line with this, all of the lessons in module 2.1.1 (cell structure) have an ongoing quiz competition where points can be won in rounds that introduced key terms and values. A quiz scoresheet is included within the resources so that the teacher can keep track of the scores over the 7 lessons in the module and the winning team can be revealed at the end of the last lesson. In this lesson, the quiz rounds are interspersed between a range of tasks which cover the following content: The use of the light microscope to observe cells The total magnification as a product of the power of the eyepiece and objective lens An introduction to the importance of staining The difference between magnification and resolution The use of the TEM The use of the SEM Due to the detail included in this lesson, it is estimated that it will take in excess of 2 hours of allocated A-level teaching time to cover the content

This lesson explains the effects of temperature increases on enzyme activity and describes how to calculate the temperature coefficient. The PowerPoint and the accompanying resource are part of the second lesson in a series of 3, which cover the content detailed in point 2.1.4 (d) [i] of the OCR A-level Biology A specification and this lesson has been specifically planned to tie in with an earlier lesson covering 2.1.4 (a, b & c) where the roles 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 modules 6 and 5. Moving forwards, the next part 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. The final part of the lesson introduces the Q10 temperature coefficient and students are challenged to apply this formula to calculate the value for a chemical reaction and a metabolic reaction to determine that enzyme-catalysed reactions have higher rates of reaction 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 is part of a lesson covering specification point 2.1.4 (d) [ii]

This fully-resourced lesson describes the effects of enzyme and substrate concentration on enzyme activity. The PowerPoint and accompanying resources are the third in a series of 3 lessons which cover the details of point 2.1.4 (d) [i] of the OCR A-level Biology A specification and students are also challenged on their recall of the details of transcription and translation as covered in module 2.1.3. The first part of the lesson describes how an increase in substrate concentration will affect the rate of reaction when a fixed concentration of enzyme is used. Time is taken to introduce limiting factors and students will be challenged to identify substrate concentration as the limiting factor before the maximum rate is attained and then they are given discussion time to identify the possible factors after this point. A series of exam-style questions are used throughout the lesson and the mark schemes are displayed to allow the students to assess their understanding and for any misconceptions to be immediately addressed. Moving forwards, the students have to use their knowledge of substrate concentration to construct a graph to represent the relationship between enzyme concentration and rate of reaction and they have to explain the different sections of the graph and identify the limiting factors. The final section of the lesson describes how the availability of enzymes is controlled in living organisms. Students will come to recognise that this availability is the result of enzyme synthesis and enzyme degradation and a SPOT THE ERRORS task is used to challenge their recall of protein synthesis. Please note that this lesson explains the Biology behind the effect of concentration on enzyme activity and not the methodology involved in carrying out such an investigation as this is covered in the lessons designed in line with point 2.1.4 (d) [ii]

This fully-resourced lesson describes the roles of enzymes in catalysing both intracellular and extracellular reactions and the mechanism of enzyme action. The engaging PowerPoint and accompanying resources have been designed to cover points 2.1.4 (a, b & c) of the OCR A-level Biology A specification and includes descriptions of Fischer’s lock and key hypothesis and Koshland’s induced-fit model as well as a focus on catalase and the digestive enzymes as intracellular and extracellular enzymes respectively. The lesson has been specifically planned to tie in with module 2.1.2 where protein structure and globular proteins were covered. This prior knowledge is tested through a series of exam-style questions along with current understanding and mark schemes are included in the PowerPoint so that students can assess their answers. Students will learn that enzymes are large globular proteins which contain an active site that consists of a small number of amino acids. Emil Fischer’s lock and key hypothesis is introduced to enable students to recognise that their specificity is the result of an active site that is complementary in shape to a single type of substrate. Time is taken to discuss key details such as the control of the shape of the active site by the tertiary structure of the protein. The induced-fit model is described so students can understand how the enzyme-susbtrate complex is stabilised and then students are challenged to order the sequence of events in an enzyme-controlled reaction. The final part of the lesson focuses on intracellular and extracellular enzymes. The students are challenged on their recall of the roles of DNA helicase and polymerase in DNA replication before they are challenged on their ability to apply their knowledge and understanding to an unfamiliar situation with questions about catalase and its role in the decomposition of hydrogen peroxide. The lesson concludes with one further set of exam-style questions that challenge their knowledge of carbohydrates, lipids and proteins from module 2.1.3 as they have to recognise some extracellular digestive enzymes from descriptions of their substrates.

This fully-resourced lesson describes the effects of enzyme and substrate concentration on the rate of enzyme-catalysed reactions. The PowerPoint and accompanying resources are the third in a series of 4 lessons which cover the details of point 3.2 (a) of the CIE A-level Biology specification. The first part of the lesson describes how an increase in substrate concentration will affect the rate of reaction when a fixed concentration of enzyme is used. Time is taken to introduce limiting factors and students will be challenged to identify substrate concentration as the limiting factor before the maximum rate is attained and then they are given discussion time to identify the possible factors after this point. A series of exam-style questions are used throughout the lesson and the mark schemes are displayed to allow the students to assess their understanding and for any misconceptions to be immediately addressed. Moving forwards, the students have to use their knowledge of substrate concentration to construct a graph to represent the relationship between enzyme concentration and rate of reaction and they have to explain the different sections of the graph and identify the limiting factors. The final section of the lesson describes how the availability of enzymes is controlled in living organisms. Students will come to recognise that this availability is the result of enzyme synthesis and enzyme degradation and a series of tasks will introduce the details of transcription and translation and therefore prepare them for the lessons in topic 6. Please note that this lesson explains the Biology behind the effect of concentration on enzyme-catalysed reactions and not the methodology involved in carrying out such an investigation as this is covered in a core practical lesson.

This fully-resourced lesson describes how the release of ADH from the pituitary gland controls mammalian plasma concentration. The engaging PowerPoint and accompanying resources have been designed to cover the detail included in point 9.9 (iv) of the Edexcel A-level Biology B specification and also includes details of the roles of the osmoreceptors in the hypothalamus. The principles of homeostasis and negative feedback were covered in an earlier lesson in topic 9, so this lesson acts to build on that knowledge and challenges them to apply their knowledge. A wide range of activities have been included in the lesson to maintain motivation and engagement whilst the understanding and prior knowledge checks will allow the students to assess their progress as well as challenge themselves to make links to other Biology topics. The lesson begins with a discussion about how the percentage of water in urine can and will change depending on the blood water potential. Students will quickly be introduced to osmoregulation and they will learn that the osmoreceptors and the osmoregulatory centre are found in the hypothalamus. A considerable amount of time is taken to study the cell signalling between the hypothalamus and the posterior pituitary gland by looking at the specialised neurones (neurosecretory cells). Links are made to the topics of neurones, nerve impulses and synapses and the students are challenged to recall the cell body, axon and vesicles. The main section of the lesson forms a detailed description of the body’s detection and response to a low blood water potential. The students are guided through this section as they are given 2 or 3 options for each stage and they have to use their knowledge to select the correct statement. The final task asks the students to write a detailed description for the opposite stimulus and this task is differentiated so those who need extra assistance can still access the work.

This fully-resourced lesson describes how the autonomic nervous system controls the heart rate. The engaging and detailed PowerPoint and accompanying resources have been designed to cover point 9.8 (i) of the Edexcel A-level Biology B specification which states that students should understand the roles of baroreceptors, chemoreceptors, the cardiac centre in the medulla oblongata and the sympathetic and parsympathetic nerves in the control. This lesson begins with a prior knowledge check where students have to identify and correct any errors in a passage about the conduction system of the heart. This allows the SAN to be recalled as this structure play an important role as the effector in this control system. Moving forwards, the three key parts of a control system are recalled as the next part of the lesson will specifically look at the range of sensory receptors, the coordination centre and the effector. Students are introduced to chemoreceptors and baroreceptors and time is taken to ensure that the understanding of the stimuli detected by these receptors is complete and that they recognise the result is the conduction of an impulse along a neurone to the brain. A quick quiz is used to introduce the medulla oblongata as the location of the cardiovascular centre. The communication between this centre and the SAN through the autonomic nervous system can be poorly understood so detailed explanations are provided and the sympathetic and parasympathetic divisions compared. The final task challenges the students to demonstrate and apply their understanding by writing a detailed description of the control and this task has been differentiated three ways to allow differing abilities to access the work

This lesson describes how the mechanisms involved in the selective reabsorption of solutes in the proximal convoluted tubule. The PowerPoint and accompanying resource have been designed to cover the first part of specification point 9.9 (iii) of the Edexcel A-level Biology B specification and builds on the knowledge gained in the previous lessons on the structure of the nephron and ultrafiltration. The lesson begins by challenging the students to recall the substances that are found in the glomerular filtrate so that each of them can be considered over the course of the rest of the lesson. Moving forwards, the first of the numerous discussion points which are included in the lesson is used to get students to predict the component of the filtrate which won’t be found in the urine when they are presented with pie charts from each of these situations. Upon learning that glucose is 100% reabsorbed, along with most of the ions and some of the water, the rest of the lesson focuses on describing the relationship between the structure of the PCT and the function of selective reabsorption. Again, this section begins by encouraging the students to discuss and to predict which structures they would expect to find in a section of the kidney if the function is to reabsorb. They are given the chance to see the structure (as shown in the cover image) before each feature is broken down to explain its importance. Time is taken to look at the role of the cotransporter proteins to explain how this allows glucose, along with sodium ions, to be reabsorbed from the lumen of the PCT into the epithelial cells. The final part of the lesson focuses on urea and how the concentration of this substance increases along the tubule as a result of the reabsorption of some of the water.

This detailed lesson describes how urea is formed in the liver by deamination and then removed from the bloodstream by ultrafiltration at the kidney. The PowerPoint and accompanying resources have been designed to cover point 9.9 (ii) of the Edexcel A-level Biology B specification. The first part of the lesson describes how deamination and the ornithine cycle forms urea. Although the students are not required to know the details of the cycle, it is important that they are aware of how the product of deamination, ammonia, is converted into urea (and why). Moving forwards, the rest of the lesson has been written to allow the students to discover ultrafiltration as a particular function and to be able to explain how the mechanisms found in the glomerulus and the Bowman’s capsule control the movement of small molecules out of the blood plasma. Key terminology is used throughout and students will learn how the combination of the capillary endothelium and the podocytes creates filtration slits that allow glucose, water, urea and ions through into the Bowman’s capsule but ensure that blood cells and plasma proteins remain in the bloodstream. A number of quiz competitions are used to introduce key terms and values in a fun and memorable way whilst understanding and prior knowledge checks allow the students to assess their understanding of the current topic and to challenge themselves to make links to earlier topics. The final task of the lesson challenges the students to apply their knowledge by recognising substances found in a urine sample that shouldn’t be present and to explain why this would cause a problem

This detailed lesson describes the gross and microscopic structure of the mammalian kidney. The engaging PowerPoint and accompanying resource have been designed to cover point 9.9 (i) of the Edexcel A-level Biology B specification. The lesson was designed to tie in with the other lessons in topic 9.9 on ultrafiltration, selective reabsorption and the control of mammalian plasma concentration and a common theme runs throughout to allow students to build their knowledge gradually and develop a deep understanding of this organ. Students will come to recognise the renal cortex and renal medulla as the two regions of the kidney and learn the parts of the nephron which are found in each of these regions. Time is taken to look at the vascular supply of this organ and specifically to explain how the renal artery divides into the afferent arterioles which carry blood towards the glomerulus and the efferent arterioles which carry the blood away. The main task of the lesson challenges the students to relate structure to function. Having been introduced to the names of each of the parts of the nephron, they have to use the details of the structures found at these parts to match the function. For example, they have to make the connection between the microvilli in the PCT as a sign that this part is involved in selective reabsorption.

This detailed lesson describes how an endotherm regulates its temperature through behaviour and also physiologically. The engaging PowerPoint and accompanying resources have been designed to cover specification point 9.9 (vii) of the Edexcel A-level Biology B specification and includes descriptions of the roles of the autonomic nervous system, thermoreceptors, hypothalamus and skin. A wide range of activities have been written into this lesson so that students remain motivated throughout and take a genuine interest in the content. Understanding checks allow the students to assess their progress whilst the prior knowledge checks on topics such as enzymes and denaturation demonstrate the importance of being able to make connections and links between topics from across the specification. In addition to these checks, quiz competitions like HAVE an EFFECT which is shown in the cover image are used to introduce key terms and values in a fun and memorable way. The lesson begins by introducing the key term, endotherm, and challenging students to use their prior knowledge and understanding of terminology to suggest what this reveals about an organism. Moving forwards, students will learn how the heat generated by metabolic reactions is used as a source of internal heat. The main part of the lesson focuses on thermoregulation in humans (mammals) and time is taken to focus on the key components, namely the sensory receptors, the thermoregulatory centre in the hypothalamus and the responses brought about by the skin. The important details of why the transfer of heat energy between the body and the environment actually leads to a decrease in temperature are explored and discussed at length to ensure understanding is complete. Students are challenged to write a detailed description of how the body detects and responds to a fall in body temperature and this task is differentiated for those students who need some extra assistance. The peripheral thermoreceptors are introduced and this leads into the final section of the lesson that considers behavioural responses in humans and other animals.

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 detailed lesson describes the the structure and function of the motor neurones that form the autonomic nervous system and is responsible for automatic responses. The engaging PowerPoint and accompanying resource have been designed to cover point 9.4 (v) of the Edexcel A-level Biology B specification and describes the sympathetic and parasympathetic divisions and how they act antagonistically. The lesson begins with a focus on the types of effectors that will be connected to the CNS by autonomic motor neurones. Students will learn that effectors which are not under voluntary control such as cardiac muscle, smooth muscle and glands will be innervated by these neurones. Moving forwards, a quick quiz competition is used to introduced ganglia as a structure which connects the two or more neurones involved in the cell signalling between the CNS and the effector. This leads into the discovery of the two divisions and students will begin to recognise the differences between the sympathetic and parasympathetic systems based on function but also structure. The remainder of the lesson looks at the differing effects of these two systems. This lesson has been written to tie in with the lesson on the organisation of the mammalian nervous system which was covered earlier in this topic

This detailed lesson describes the formation and effects of excitatory and inhibitory postsynaptic potentials . The PowerPoint has been designed to cover point 9.5 (v) of the Edexcel A-level Biology B specification. This is a topic which is generally poorly understood by students or brushed over so considerable time has been taken to design the activities to motivate the students so that the content is memorable whilst still being covered in detail. Links are continually made to earlier topics in this topic such as synapses and generator potentials but also to topics covered in the previous year. The lesson begins by challenging the students to recognise a description of generator potential and they will then discover that this is also known as an EPSP. Students will recall that a small depolarisation may not lead to the opening of the voltage gated channels and therefore the full depolarisation which is needed for the initiation of an action potential and will discuss how this problem could be overcome. Lots of discussion points like this are included in the lesson to encourage the students to challenge and debate why a particular process of mechanism occurs. Students will therefore learn that EPSPs can be combined and this is known as summation. A quiz round is used to introduce temporal and spatial summation. Moving forwards, students are presented with a number of examples where they have to decide why type of summation is involved. Again, the lesson has been written to include real-life examples such as chronic pain conditions so the chances of the content sticking is increased. The final part of the lesson introduces IPSPs and the effect of these on summation and action potentials is discussed.

This lesson describes the relationship between the structure and function of a synapse, focusing on acetylcholine as the neurotransmitter. The engaging and detailed PowerPoint and accompanying resources have been designed to cover the content of point 9.5 (iv) of the Edexcel A-level Biology B specification. The lesson begins by using a version of the WALL (as shown in the cover image) which asks the students to group 12 words into three groups of 4. Not only will this challenge their prior knowledge from topics earlier in this topic but it will also lead to the discovery of four of the structures that are found in a synapse. Moving forwards, students are introduced to acetylcholine as the neurotransmitter involved at cholinergic synapses and they will start to add labels to the structures found in the pre-synaptic bulb. Time is taken to focus on certain structures such as the voltage gated channels as these types of channel were met previously when looking at the depolarisation of a neurone. There is plenty of challenge and discovery as students are pushed to explain why organelles like mitochondria would be found in large numbers in the bulb. With this process being a cascade of events, a bullet point format is used to ensure that the key content is taken in by the students and again key points like exocytosis and the action of acetylcholinesterase are discussed further. Understanding checks and prior knowledge checks are included throughout the lesson so that students can not only assess their progress against the current topic but also be challenged to make links to earlier topics.

This fully-resourced lesson explains why the speed of transmission along myelinated axons is greater than along non-myelinated axons. The PowerPoint and accompanying resources have been designed to cover point 9.5 (iii) of the Edexcel A-level Biology B specification which states that students should understand the role of saltatory conduction in the transmission of action potentials. A wide range of activities have been written into this resource to maintain the motivation of the students whilst ensuring that the detail is covered in real depth. Interspersed with the activities are understanding checks and prior knowledge checks to allow the students to not only assess their understanding of the current topic but also challenge themselves to make links to earlier topics such as the movement of ions across membranes and biological molecules. Time at the end of the lesson is also given to future knowledge such as the involvement of autonomic motor neurones in the stimulation of involuntary muscles. Over the course of the lesson, students will learn and discover the myelin sheath wrapped around the axons of sensory and motor neurones allows these neurones to conduct impulses quickly between receptors and the CNS and between the CNS and effectors. There is a focus on this myelin sheath and specifically how the insulation is not complete all the way along which leaves gaps known as the nodes of Ranvier which allow the entry and exit of ions. Saltatory conduction is poorly understood (and explained) by a lot of students so time is taken to look at the way that the action potential jumps between the nodes and this is explained further by reference to local currents. The rest of the lesson focuses on the other two factors which are axon diameter and temperature and students are challenged to discover these two by focusing on the vampire squid.