This detailed lesson describes the different levels of protein structure and focuses on the bonds that hold these molecules in shape. Both the engaging PowerPoint and accompanying resources have been designed to cover specification point 2.3 (b) of the CIE International A-level Biology course and makes continual links to previous lessons such as amino acids & peptide bonds as well as to upcoming lessons like enzymes and antibodies. The start of the lesson focuses on the formation of a peptide bond during a condensation reaction so that students can understand how a dipeptide is formed and therefore how a polypeptide forms when multiple reactions occur. The main part of the lesson describes the different levels of protein structure. A step by step guide is used to demonstrate how the sequences of bases in a gene acts as a template to form a sequence of codons on a mRNA strand and how this is translated into a particular sequence of amino acids known as the primary structure. The students are then challenged to apply their understanding of this process by using three more gene sequences to work out three primary structures and recognise how different genes lead to different sequences. Moving forwards, students will learn how the order of amino acids in the primary structure determines the shape of the protein molecule, through its secondary, tertiary and quaternary structure and time is taken to consider the details of each of these. There is a particular focus on the different bonds that hold the 3D shape firmly in place and a quick quiz round then introduces the importance of this shape as exemplified by enzymes, antibodies and hormones. Students will see the differences between globular and fibrous protein and again biological examples are used to increase relevance. The lesson concludes with one final quiz round called STRUC by NUMBERS where the students have to use their understanding of the protein structures to calculate a numerical answer.

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.

Water is very important for living organisms because of its numerous properties and this lesson focuses on its role as a solvent in transport. The engaging and detailed PowerPoint and accompanying worksheet have been designed to cover point 1.1 of the Edexcel International A-level Biology specification and also explains the importance of the dipole nature for this role in transport. A mathematical theme runs throughout the lesson as students have to match the numbers calculated in the starter task to water statistics, such as the percentage of the volume of blood plasma that is water. This has been included to try to increase the relevance of each property so that it can be described in a biological context. Time is taken at the beginning of the lesson to describe the structure of water in terms of the covalent bonds between the oxygen and hydrogen atoms as well as the hydrogen bonds which form between molecules because of its polarity. Students will understand how water is a solvent which means that it is critical for transport in animals, a topic covered in the next few lessons but also for transport in plants as discussed in topic 4. The high heat capacity and latent heat of vaporisation of water is also discussed and explained through the examples of thermoregulation and the maintenance of a stable environment for aquatic animals. The final part of the lesson focuses on the involvement of water in condensation and hydrolysis reactions, two reactions which must be well understood for topic 1 and 2 and the formation and breakage of polysaccharides, lipids, polypeptides and polynucleotides.

This fully-resourced lesson describes how the eukaryotic cells of complex multicellular organisms become specialised for specific functions. The detailed and engaging PowerPoint and accompanying resources have been designed to cover the 3rd part of point 2.1.1 of the AQA A-level Biology specification and also describes how these specialised cells are organised into tissues, organs and organ systems. The start of the lesson focuses on the difference in the SA/V ratio of an amoeba and a human in order to begin to explain why the process of differentiation is critical for multicellular organisms. Students will discover that a zygote is a stem cell which can express all of the genes in its genome and divide by mitosis. Time is then taken to introduce gene expression as this will need to be understood in the later topics of the course. Moving forwards, the lesson uses the process of haematopoiesis from haematopoietic stem cells to demonstrate how the red blood cell and neutrophil differ significantly in structure despite arising from the same cell along the same cell lineage. A series of exam-style questions will not only challenge their knowledge of structure but also their ability to apply this knowledge to unfamiliar situations. These differences in cell structure is further exemplified by the epithelial cells of the respiratory tract and students will understand why the shape and arrangement of these cells differ in the trachea and alveoli in line with function. The link between specialised cells and tissues is made at this point of the lesson with these examples of epithelium and students will also see how tissues are grouped into organs and then into organ systems. The remainder of the lesson focuses on specialised plant cells and the differing shapes and features of the palisade and spongy mesophyll cells and the guard cells are covered at length and in detail. Step by step guides will support the students so that they can recognise the importance of the structures and links are made to upcoming topics such as diffusion, active transport and osmosis so that students are prepared for these when covered in the future. This lesson has been written to continually tie in with the previous two lessons in this specification point which are uploaded under the titles of the structure of eukaryotic animal and plant cells.

Adenosine triphosphate is the universal energy currency and this lesson focuses on the role of this molecule in cell. The PowerPoint has been designed to cover point1.2 © of the CIE International A-level Biology specification and also explains how ATP must be hydrolysed to release energy and then re-synthesised during respiration and photosynthesis in the mitochondria and chloroplast respectively. As students were introduced to the structure of DNA and RNA at GCSE, the start of this lesson challenges them on their knowledge of these polynucleotides so that they can recognise that ATP consists of adenine, ribose and three phosphate groups. In order to release the stored energy, ATP must be broken down and students will be given time to discuss which reaction will be involved as well as the products of this reaction. Time is taken to describe how the hydrolysis of ATP can be coupled to energy-requiring reactions within cells and the examples of active transport and skeletal muscle contraction are used as these are covered in greater detail in topics 4 and 15. The final part of the lesson considers how ATP must be re-synthesised and students will learn that this occurs in the mitochondria and chloroplast during aerobic respiration and photosynthesis respectively.

This lesson describes and explains the processes of simple diffusion and facilitated diffusion. The PowerPoint and accompanying resources have been designed to cover the first part of specification point 4.2 (a) of the CIE International A-level Biology course and the factors that increase the rate of diffusion are covered along with the limitations imposed by the phospholipid bilayer and the role of channel and carrier proteins. The structure and properties of cell membranes was covered in topic 4.1 so this lesson has been written to include continual references to the content of that lesson. This enables links to be made between the movement across a cell membrane with the concentration gradient, the parts of the membrane that are involved and any features that may increase the rate at which the molecules move. A series of questions about the alveoli are 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

This fully-resourced lesson explores the contributions of chromosome mutations to genetic variation. The engaging PowerPoint and accompanying worksheets have been designed and written to cover the part of point 6.1.2 (a) of the OCR A-level Biology A specification which states that students should be able to demonstrate and apply their knowledge and understanding of the contribution of genetic factors to phenotypic variation Over the course of the lesson, students will encounter a number of chromosome mutations and see the conditions which they cause. Time is taken to look at non-disjunction and how this can result in Down, Turner’s and Klinefelter’s syndromes. Students are guided through a description of the formation of gametes and zygotes with abnormal numbers of chromosomes before being challenged to describe the formation of a zygote with Turner’s syndrome. Moving forwards, translocation and polyploidy are also discussed. Progress checks are written into the lesson at regular intervals, that not only check the learning from this lesson but also from related topics (such as meiosis) and this enables the students to constantly assess their understanding.

This fully-resourced lesson describes how DNA is replicated during interphase of the cell cycle and explains why it is known as semi-conservative replication. Both the detailed PowerPoint and accompanying resources have been designed to cover the details of point 2.1.3 (e) of the OCR A-level Biology A specification and the occurrence of spontaneous mutations is also discussed in the latter part of the lesson. As detailed in the specification, the focus of this lesson is the role of the enzymes DNA helicase and polymerase and students are also introduced to DNA ligase to enable them to understand how this enzyme functions to join the nucleic acid fragments. Time is taken to explain key details such as the assembly of strands in the 5’-to-3’ direction so that the continuous manner in which the leading strand is synthesised can be compared against that of the lagging strand. The students are constantly challenged to make links to previous topics such as DNA structure, phosphorylated nucleotides and hydrolysis reactions through a range of exam questions and answers are displayed so any misconceptions are quickly addressed. The final part of the lesson focuses on the occurrence of mistakes by DNA polymerase and also on the quantity of DNA in the cell following replication so that future links can be made to the cell cycle (as covered in module 2.1.6)

This is an engaging revision lesson which uses a range of exam questions, understanding checks, quick differentiated tasks and quiz competitions to allow students to assess their knowledge of the topic of cells and related topics as covered in the GCSE Biology and GCSE Combined Science courses. As cells are the building blocks of living organisms, a strong understanding of this topic is critical for the success of a student on these two courses. The following topics are covered in this revision lesson: The key differences between eukaryotic and prokaryotic cells The structure of a bacterial cell Specialised cells The individual functions of the organelles Calculating size Students will be engaged through the range of activities which includes quiz competitions such as “CELL, CELL, CELL” where students have to compete to identify specialised cells from descriptions. This lesson can be used at any time during the year as a revision material, in the lead up to mocks or as a final revision lesson before the GCSE terminal exams.

This is an engaging and fully-resourced revision lesson which uses a range of exam questions, understanding checks, quiz tasks and quiz competitions to enable students to assess their understanding of the content within topic 1 (Key concepts in Biology) of the Edexcel GCSE Biology 9-1 specification. The specification points that are covered in this revision lesson include: Explain how the sub-cellular structures of eukaryotic and prokaryotic cells are related to their functions Describe how specialised cells are adapted to their function Know that changes in microscope technology, including electron microscopy, have enabled us to see cell structures and organelles with more clarity and detail than in the past Demonstrate an understanding of the relationship between quantitative units in relation to cells Explain how substances are transported into and out of cells, including by diffusion, osmosis and active transport Core Practical: Investigate osmosis in potatoes Calculate percentage gain and loss of mass in osmosis The students will thoroughly enjoy the range of activities, which include quiz competitions such as “CELL, CELL, CELL” where they have to compete to quickly identify specialised cells from their descriptions whilst crucially being able to recognise the areas of this topic which need their further attention. This lesson can be used as revision resource at the end of the topic or in the lead up to mocks or the actual GCSE exams.