This lesson describes how the expression of a gene mutation impairs the functioning of the gaseous and digestive systems in people with cystic fibrosis. The detailed PowerPoint and accompanying worksheets have primarily been designed to cover points 2.12 (ii) and 2.14 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification but also challenges the students on their knowledge of previously-covered topics including monohybrid inheritance, protein synthesis, genetic code and blood clotting as well as making links to the upcoming topics of loci, organisation of multicellular organisms and post-transcriptional changes.
The main focus of the lesson is the CFTR gene and the functions of the ion channel that is synthesised when this gene is expressed. As well as explaining that this channel allows chloride ions to flow across the apical membrane of the epithelial cells, time is taken to emphasise the importance of its inhibition on the ENaC, which prevents the flow of sodium ions back into the cells. A step by step guide is then used to describe the sequence of events that result in mucus which is motile and can be moved by the wafting action of the cilia in healthy individuals. This leads into the section of the lesson which considers the inheritance of cystic fibrosis in an autosomal recessive manner and then focuses on the change in the primary structure of the channel which results from one of over 1500 different gene mutations. Again, the students are guided through the events that lead to the depletion of the apical surface liquid and the cilia being unable to move the viscous mucus. Although the majority of the lesson is described with reference to the gaseous exchange system, the impaired functioning of the digestive system in terms of the blockage of the pancreas and liver secretions is considered and discussed and the students are challenged on their understanding through a range of exam-style questions.
All of the questions included in the lesson have mark schemes which are embedded into the PowerPoint and this allows the students to assess their progress.
Due to the detailed content of this lesson, it is estimated that it will take in excess of 3 hours of allocated A-level teaching time to cover
Get this resource as part of a bundle and save up to 36%
A bundle is a package of resources grouped together to teach a particular topic, or a series of lessons, in one place.
Nucleic acids, Genetics and Inheritance (Edexcel SNAB)
This lesson bundle contains 16 lessons which have been designed to cover the Pearson Edexcel A-level Biology A (Salters Nuffield) specification points which focus on the structure of DNA and RNA, their roles in replication and protein synthesis, and genetics and inheritance. The lesson PowerPoints are highly detailed, and along with their accompanying worksheets, they have been planned at length to contain a wide range of engaging tasks which cover the following A-level Biology content found in topics 2, 3 and 6 of the course: 2.5 (i): Know the basic structure of mononucleotides (deoxyribose or ribose linked to a phosphate and a base, including thymine, uracil, cytosine, adenine or guanine) and the structures of DNA and RNA (polynucleotides composed of mononucleotides linked through condensation reactions) 2.5 (ii): Know how complementary base pairing and the hydrogen bonding between two complementary strands are involved in the formation of the DNA double helix 2.6 (i): Understand the process of protein synthesis (transcription) including the role of RNA polymerase, translation, messenger RNA, transfer RNA, ribosomes and the role of start and stop codons 2.6 (ii): Understand the roles of the DNA template (antisense) strand in transcription, codons on messenger RNA and anticodons on transfer RNA 2.7: Understand the nature of the genetic code 2.8: Know that a gene is a sequence of bases on a DNA molecule that codes for a sequence of amino acids in a polypeptide chain 2.11 (i): Understand the process of DNA replication, including the role of DNA polymerase 2.12 (i): Understand how errors in DNA replication can give rise to mutations 2.12 (ii): Understand how cystic fibrosis results from one of a number of possible gene mutations 2.13 (i): Know the meaning of the terms: gene, allele, genotype, phenotype, recessive, dominant, incomplete dominance, homozygote and heterozygote 2.13 (ii): Understand patterns of inheritance, including the interpretation of genetic pedigree diagrams, in the context of monohybrid inheritance 2.14: Understand how the expression of a gene mutation in people with cystic fibrosis impairs the functioning of the gaseous exchange, digestive and reproductive systems 2.15 (i): Understand the uses of genetic screening, including the identification of carriers, pre-implantation genetic diagnosis (PGD) and prenatal testing, including amniocentesis and chorionic villus sampling 2.15 (ii): Understand the implications of prenatal genetic screening 3.8 (i): The loci is a location of genes on a chromosome 3.8 (ii): The linkage of genes on a chromosome and sex linkage 3.12: Understand how cells become specialised through differential gene expression, producing active mRNA leading to synthesis of proteins, which in turn control cell processes or determine cell structure in animals and plants, including the lac operon 3.14 (i): Phenotype is an interaction between genotype and the environment 3.15: Understand how some phenotypes are affected by multiple alleles for the same gene at many loci (polygenic inheritance) as well as the environment and how this can give rise to phenotypes that show continuous variation 6.4: Know how DNA can be amplified using the polymerase chain reaction (PCR) 6.10: Understand how one gene can give rise to more than one protein through posttranscriptional changes to messenger RNA (mRNA).
Topic 2: Genes and Health (Pearson Edexcel SNAB)
Some of the key biological topics are covered in topic 2 of the Pearson Edexcel A-level Biology A (Salters Nuffield) course and include the transport of materials across cell membranes, DNA structure and replication, protein synthesis and monohybrid inheritance. In line with this, many hours of intricate planning have gone into the design of all of the 19 lessons that are included in this bundle to ensure that the content is covered in detail, understanding is constantly checked to immediately address misconceptions and that engagement is high. This is achieved through the wide variety of tasks in the PowerPoints and accompanying worksheets which include exam-style questions with clear answers, discussion points, differentiated tasks and quick quiz competitions. The following specification points are covered by the lessons within this bundle: * The properties of gas exchange surfaces in living organisms * Understand how the rate of diffusion is dependent on these properties and can be used in the calculation of the rate of diffusion by Fick's law * Adaptations of the mammalian lung for rapid gaseous exchange * Structure and properties of cell membranes * Simple and facilitated diffusion as methods of passive transport * The involvement of ATP and carrier proteins in active transport, endocytosis and exocytosis * The basic structure of mononucleotides * The structures of DNA and RNA * The process of protein synthesis * The roles of the template strand, mRNA and tRNA * The nature of the genetic code * A gene is a sequence of bases on DNA that codes for the amino acid sequence of a polypeptide * The basic structure of an amino acid * The formation of polypeptides and proteins * The primary, secondary, tertiary and quaternary structure of proteins * Globular and fibrous proteins using haemoglobin and collagen as examples * The mechanism of action and the specificity of enzymes * Enzymes are biological catalysts that reduce activation energy * The process of DNA replication * Errors in DNA replication can give rise to mutations * The meaning of key genetic terms * Patterns of inheritance, in the context of monohybrid inheritance * Understand how the expression of a gene mutation in people with cystic fibrosis impairs the functioning of the gaseous exchange, digestive and reproductive systems * Understand the uses and implications of genetic screening and prenatal testing Due to the detail included in each of these lessons, it is estimated that it will take in excess of 2 months of allocated teaching time to cover the content. If you would like to see the quality of the lessons, download the gas exchange surfaces, cell membranes, transcription, globular and fibrous proteins, monohybrid inheritance and cystic fibrosis lessons as these have been shared for free
Something went wrong, please try again later.
Thank you, very useful for an old teacher to a new course. Great resource.
Thanks very much for sharing this It is a great help. Going through the ppt I recognised your style from some revision materials I purchased some time back which were also very good. We are very short of teaching time so I will abbreviate it but still keep the logical steps which are very well put.
Report this resourceto let us know if it violates our terms and conditions.
Our customer service team will review your report and will be in touch.