This lesson describes the roles of the hypothalamus, posterior pituitary, ADH and collecting ducts in osmoregulation. The PowerPoint and accompanying resources have been planned to cover the content of point (8) of topic 14.1 of CIE A-level biology specification (for assessment in 2025-27). Students covered the principles of homeostasis and negative feedback in the first lesson in this topic, 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 lesson explains how the structure of the Bowman’s capsule leads to the formation of glomerular filtrate by ultrafiltration. The PowerPoint and accompanying resource are part of the 1st lesson in a series of two lessons which have been planned to cover the content of points (6 and 7) of topic 14.1 of the CIE A-level Biology specification (for assessment in 2025-27) The lesson provides students with the opportunity to gauge a deep understanding of ultrafiltration and 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 The 2nd lesson in this series covers selective reabsorption.

This lesson describes the structure and function of sensory and motor neurones as well as the role of intermediate neurones. The PowerPoint and accompanying resources have been planned to cover the content of point (3) of topic 15.1 of the CIE A-level Biology specification (for assessment in 2025 - 27) and also focuses on the organisation of the nervous system to support students with their understanding of upcoming content in this topic. The PowerPoint has been designed to contain a wide range of activities that are interspersed between understanding and prior knowledge checks that allow the students to assess their progress on the current topics as well as challenge their ability to make links to topics from earlier in the modules. Quiz competitions like SAY WHAT YOU SEE are used to introduce key terms in a fun and memorable way. The students will be able to compare these neurones based on their function but also distinguish between them based on their structural features. Time is taken to introduce the importance of the myelin sheath that is present in both neurones to allow saltatory conduction to occur.

This lesson describes the ultrastructure of striated muscle with particular reference to sarcomere structure. The PowerPoint and accompanying resource have been planned to cover point (11) of topic 15.1 of the CIE A-level Biology specification. There are a wide range of key terms and regions in this topic so they are introduced in a fun and memorable way using a variety of activities that include quiz competitions. These are followed by understanding checks to allow students to assess their progress and ensure that any misconceptions are addressed. Connections are made to the upcoming topic of the sliding filament model as the students discover that despite the shortening of the sarcomere (and I band and H zone) during contraction, the fact that the A band remains the same length shows how the filaments slide over each other. The two main tasks of the lesson challenge the students to label a diagram of a sarcomere and then the microscope image as shown in the cover picture.

This lesson describes the structure of a cholinergic synapse and outlines the role of these connections in the nervous system. The fully-resourced lesson has been designed to cover the content of point (9) of topic 15.1 of the CIE A-level biology specification (for assessment in 2025-27). The majority of the lesson uses the cholinergic synapse as the example but other neurotransmitters are considered at the end of the lesson to provide the students with a wider view of this topic. One of the tasks near the beginning of the lesson challenges students to identify 3 terms from a WALL of key terms that could follow synaptic, having been introduced to the synaptic cleft on the previous slide. Not only will this challenge their prior knowledge from lessons earlier in topic 15 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. The final part of the lesson challenges the application aspect of the subject as students are introduced to unfamiliar situations in terms of synapses with new drugs like MDMA and are asked to work out and explain how these affect the nervous transmission. 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 see whether they can make links to earlier topics.

This lesson explains why the conduction of an impulse along myelinated neurones is faster than along unmyelinated neurones. The PowerPoint and accompanying resources have been written to cover point (7) of topic 15.1 of the CIE A-level Biology specification. A wide range of activities are included in this lesson to maintain the motivation of the students whilst ensuring that the detail is covered in 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. Over the course of the lesson, students consider the structure of the myelin sheath and specifically how the electrical insulation is not complete all the way along. This leaves gaps, known as the nodes of Ranvier, which allow the entry and exit of ions. Saltatory conduction can be poorly 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.

This lesson describes the role of abscisic acid in the closure of stomata during times of water stress, including the role of calcium ions. The PowerPoint and accompanying resources have been planned to cover the content of point (4) of topic 14.2 of the CIE A-level biology specification (for assessment in 2025-27). The lesson begins with an introduction of water stress and the description of the need for plants to adapt to these conditions because they can’t flee like animals can. A step-by-step guide underpins the lesson, consisting of 8 key steps in the mechanism. A series of tasks run alongside this, supporting the students with their understanding of key substances, such as abscisic acid, calcium ions, and potassium ions. There are multiple understanding checks, with answers embedded into the PowerPoint, to allow students to assess their own progress. There are also prior knowledge checks which encourage students to make links to previously covered content, including the response to a low blood glucose, and also the role of ions in living organisms. This lesson has been specifically designed to follow the lesson on guard cells and stomata, which is also uploaded.