4th Sep '25

Schemes of Work

B2
- B2.4
  - Lesson 01 - How are living things classified? Lesson Plan Lesson Title
    - Traditionally living things have been classified into groups depending on their structure and characteristics in a system developed by Carl Linnaeus
      - Suggested Activity:
        Exhibition of organisms to classify, use post-it notes to explain groupings – observe and discuss choices made by other groups.
        Equipment Required:
        classification cards (pictures of animals)
    - Linnaeus classified living things into kingdom, phylum, class, order, family, genus and species.
      - Suggested Activity:
        Compare the classification of related and unrelated organisms using the Linnaeus system.
    - Organisms are named by the binomial system of genus and species.
      - Suggested Activity:
        Look at the variety of names given to the same plant and discuss why the binomial system is more useful.
    - Students should be able to use information given to show understanding of the Linnaean system.
    - Students should be able to describe the impact of developments in biology on classification systems.
    - As evidence of internal structures became more developed due to improvements in microscopes, and the understanding of biochemical processes progressed, new models of classification were proposed. (WS) Understand how scientific methods and theories develop over time.
    - Due to evidence available from chemical analysis there is now a ?three- domain system? developed by Carl Woese. In this system organisms are divided into:
      ? archaea (primitive bacteria usually living in extreme environments)
      ? bacteria (true bacteria)
      ? eukaryota (which includes protists, fungi, plants and animals).
      - Suggested Activity:
        Watch BBC video clip about chemical analysis and its use in classifying organisms (see resources).
        http://www.bbc.co.uk/education/clips/zhb3cdm
    - Evolutionary trees are a method used by scientists to show how they believe organisms are related. They use current classification data for living organisms and fossil data for extinct organisms.
    - Students should be able to interpret evolutionary trees (WS)
  - Lesson 02 - How is variation in organisms created? Lesson Plan Lesson Title
    - Students should be able to describe simply how the genome and its interaction with the environment influence the development of the phenotype of an organism
      - Suggested Activity:
        Discuss why organisms of the same species show variation. Use the terms: genetic and environmental variation, continuous and discontinuous variation.
    - Differences in the characteristics of individuals in a population is called variation and may be due to differences in:
      - the genes they have inherited (genetic causes)
      - the conditions in which they have developed (environmental causes)
      - a combination of genes and the environment
      - Suggested Activity:
        List different characteristics in which there is variation.
        Include in the table whether each characteristic is due to genetic or environmental causes, or both.
    - Students should be able to state that there is usually extensive genetic variation within a population of a species
    - A recessive allele is only expressed if two copies are present (therefore no dominant allele present).
    - (Biology only) Mutations occur continuously. Very rarely a mutation will lead to a new phenotype. If the new phenotype is suited to an environmental change it can lead to a relatively rapid change in the species. There are links with this content to
      Speciation (biology only).
    - Students should be able to describe evolution as a change in the
      inherited characteristics of a population over time through a process of natural selection which may result in the formation of a new species.
    - The theory of evolution by natural selection states that all species of living things have evolved from simple life forms that first developed
      more than three billion years ago.
    - Students should be able to explain how evolution occurs through natural selection of variants that give rise to phenotypes best suited to their environment. Use the theory of evolution by natural
      selection in an explanation.
    - If two populations of one species become so different in phenotype
      that they can no longer interbreed to produce fertile offspring they have formed two new species.
  - Lesson 03 - Is genetic engineering a good thing? What are the impacts of selective breeding? Lesson Plan Lesson Title
    - Students should be able to explain the impact of selective breeding of food plants and domesticated animals.
    - Selective breeding (artificial selection) is the process by which humans breed plants and animals for particular genetic characteristics. Humans have been doing this for thousands of years since they first bred food crops from wild plants and domesticated animals.
      - Suggested Activity:
        Images of different dogs. Students ‘breed’ and name a new dog from selecting any 2 – draw a picture of their new breed.
    - Selective breeding involves choosing parents with the desired characteristic from a mixed population. They are bred together. From the offspring those with the desired characteristic are bred together. This continues over many generations until all the offspring show the desired characteristic.
      - Suggested Activity:
        Draw a flow diagram to explain the steps involved in selective breeding.
    - The characteristic can be chosen for usefulness or appearance:
      ? Disease resistance in food crops.
      ? Animals which produce more meat or milk.
      ? Domestic dogs with a gentle nature.
      ? Large or unusual flowers.
      - Suggested Activity:
        Give examples of characteristics that are selectively bred in plants and animals and say why they are there - Table?
    - Selective breeding can lead to ?inbreeding? where some breeds are particularly prone to disease or inherited defects.
      - Suggested Activity:
        Discuss the advantages and risks of selective breeding in plants and animals.
        Consider the social, economic and ethical implications of selective breeding.
        Debate: should people be allowed to breed dogs?
    - Evidence for Darwin's theory is now available as it has been shown
      that characteristics are passed on to offspring in genes. There is further evidence in the fossil record and the knowledge of how resistance to antibiotics evolves in bacteria.
  - Lesson 04 - How did a monk help us understand genetics? Lesson Plan Lesson Title
    - Students should be able to describe the development of our understanding of genetics including the work of Mendel
    - Students should be able to understand why the importance of Mendel's discovery was not recognised until after his death.
    - In the mid-19th century Oregor Mendel carried out breeding experiments on plants. One of his observations was that the inheritance of each characteristic is determined by ?units? that are passed on to descendants unchanged.
      - Suggested Activity:
        Watch a video clip of Mendel’s experiments (see resources).
        Video clip: BBC Bitesize –http://www.bbc.co.uk/education/clips/zwx4wmn
        
        Use a model to explain genetic inheritance in pea plants and using unfamiliar information.
    - In the late 19th century behaviour of chromosomes during cell division was observed
      - Suggested Activity:
        Draw and label genetic diagrams to explain Mendel’s experiments.
    - Our current understanding of genetics has developed over time.
    - In the early 20th century it was observed that chromosomes and Mendel?s ?units? behaved in similar ways. This led to the idea that the ?units?, now called genes, were located on chromosomes. There are links with this content to Oenetic inheritance.
    - In the mid-20th century the structure of DNA was determined and the mechanism of gene function worked out. There are links with this content to Oenetic inheritance.
      - Suggested Activity:
        Research the main developments in the understanding of inheritance and draw a timeline.
    - This scientific work by many scientists led to the gene theory being developed. There are links with this content to Oenetic inheritance.
  - Lesson 05 - Is genetic engineering a good thing? Lesson Plan Lesson Title
    - Students should be able to describe genetic engineering as a process which involves modifying the genome of an organism by introducing a gene from another organism to give a desired characteristic
    - An example of genetic engineering is plant crops have been genetically engineered to be resistant to diseases or to produce bigger better fruits.
    - Bacterial cells have been genetically engineered to produce useful
      substances such as human insulin to treat diabetes. There are links
      with this content to role of biotechnology. (biology only).
    - Students should be able to explain the potential benefits and risks of genetic engineering in agriculture and in medicine and that some people have objections
    - In genetic engineering, genes from the chromosomes of humans and other organisms can be ?cut out? and transferred to cells of other organisms.
      - Suggested Activity:
        Brainstorm what the terms genetic engineering, genetic modification and gene therapy mean.
        List examples of genetic engineering.
    - Crops that have had their genes modified in this way are called genetically modified (GM) crops.
    - GM crops include ones that are resistant to insect attack or to herbicides.
    - GM crops generally show increased yields.
    - Concerns about GM crops include the effect on populations of wild flowers and insects. Some people feel the effects of eating GM crops on human health have not been fully explored.
      - Suggested Activity:
        Research advantages and disadvantages of GM crops. What characteristics may be modified? Produce a web page or a table of benefits versus concerns.
    - Modern medical research is exploring the possibility of genetic modification to overcome some inherited disorders
    - (HT only) Students should be able to describe the main steps in the
      process of genetic engineering.
    - (HT only) In genetic engineering:
      - enzymes are used to isolate the required gene; this gene is inserted into a vector, usually a bacterial plasmid or a virus
      - the vector is used to insert the gene into the required cells
      - genes are transferred to the cells of animals, plants or
      microorganisms at an early stage in their development so that they
      develop with desired characteristics. Interpret information about genetic engineering techniques and to make informed judgements about issues concerning cloning and genetic engineering, including OM crops.
      - Suggested Activity:
        Use a model to describe genetic engineering techniques.
        EW : How is human insulin is produced by bacteria and what advantages are there of using this over porcine insulin.
  - Lesson 06 - What are the ways, benefits and risks of cloning? Lesson Plan Lesson Title
    - Tissue culture: using small groups of cells from part of a plant to grow
      identical new plants. This is important for preserving rare plant species or commercially in nurseries.
    - Cuttings: an older, but simple, method used by gardeners to produce many identical new plants from a parent plant.
      - Suggested Activity:
        Discuss plant cloning techniques and why they are used.
        Take cuttings of different plants.
        Produce cauliflower clones – follow guidance from Science and Plants for Schools (SAPS). Observe growth in later lesson.
        Evaluate the use of cuttings and tissue culture to clone plants.
        
        http://www.saps.org.uk/secondary/teaching-resources/706-cauliflower-cloning-tissue-culture-and-micropropagation
        Equipment Required:
        Cuttings:
        scissors
        plants, eg geraniums or spider plants
        •pots &,compost
    - Embryo transplants: splitting apart cells from a developing animal
      embryo before they become specialised, then transplanting the identical embryos into host mothers.
      - Suggested Activity:
        Produce and evaluate a model to describe embryo transplants.
    - Explain the potential benefits and risks of cloning in agriculture and in medicine and that some people have ethical objections.
      - Suggested Activity:
        GF : Evaluate the effect that human cloning could have on the social, economic and cultural environment of the world if ti were to be legalised.
    - The process of adult cell cloning:
      ? The nucleus is removed from an unfertilised egg cell.
      ? The nucleus from an adult body cell, such as a skin cell, is inserted into the egg cell.
      ? An electric shock stimulates the egg cell to divide to form an embryo.
      ? These embryo cells contain the same genetic information as the adult
      skin cell.
      ? When the embryo has developed into a ball of cells, it is inserted into
      the womb of an adult female to continue its development.
      - Suggested Activity:
        Use a model to describe adult cell cloning.
  - Lesson 07 - Who is Charles Darwin and what did he do for science? Lesson Plan Lesson Title
    - Charles Darwin, as a result of observations on a round the world
      expedition, backed by years of experimentation and discussion and linked to developing knowledge of geology and fossils, proposed the theory of evolution by natural selection.
      - Suggested Activity:
        Look at exhibition to show the wide variety of organisms that live, or have lived, on Earth.
        Discuss how they were all formed.
    - Students should appreciate that the theory of evolution by natural
      selection developed over time and from information gathered by many scientists.
    - Darwin published his ideas in On the Origin of Species (1859). There was much controversy surrounding these revolutionary new ideas.
    - Theory of evolution by natural selection invovles: ? Individual organisms within a particular species show a wide range of
      variation for a characteristic.
      ? Individuals with characteristics most suited to the environment are more likely to survive to breed successfully.
      ? The characteristics that have enabled these individuals to survive are
      then passed on to the next generation.
      - Suggested Activity:
        Draw a flow diagram to explain natural selection.
    - The theory of evolution by natural selection was only gradually accepted because:
      ? the theory challenged the idea that Ood made all the animals and
      plants that live on Earth
      ? there was insufficient evidence at the time the theory was published
      to convince many scientists
      ? the mechanism of inheritance and variation was not known until
      50 years after the theory was published.
  - Lesson 08 - How do new species form? Lesson Plan Lesson Title
    - Other theories, including that of Jean-Baptiste Lamarck, are based
      mainly on the idea that changes that occur in an organism during its
      lifetime can be inherited. We now know that in the vast majority of cases this type of inheritance cannot occur. A study of creationism is not required.
      - Suggested Activity:
        Research and produce report on evolutionary theories, eg Darwin, Wallace and Lamarck.
        
        Compare the different theories and suggest reasons for these differences – turn into a ‘Question Time’ style role play.
    - Students should be able to describe the work of Darwin and Wallace in the development of the theory of evolution by natural selection
    - Students should be able to explain the impact of these ideas on biology
    - Alfred Russel Wallace independently proposed the theory of evolution by natural selection. He published joint writings with Darwin in 1858 which prompted Darwin to publish On the Origin of Species (1859) the following year.
      - Suggested Activity:
        Research the work of Alfred Russel Wallace (see resources).
        Produce a flow diagram or cut-out to illustrate how new species arise
    - Wallace worked worldwide gathering evidence for evolutionary theory. He is best known for his work on warning colouration in animals and his theory of speciation.
    - Alfred Wallace did much pioneering work on speciation but more evidence over time has led to our current understanding of the theory of speciation
      - Suggested Activity:
        Discuss organisms that are only found in or are endemic to eg Australia, Madagascar and ask why this is. Support with projected images or video clips.
    - Students should be able to describe the steps which give rise to new species. The theory of speciation has developed over time
  - Lesson 09 - Where do fossils come from? Lesson Plan Lesson Title
    - Students should be able to describe the evidence for evolution including fossils and antibiotic resistance in bacteria.
      - Suggested Activity:
        Discuss the evidence we have to support Darwin’s theory and present in a suitable format.
    - The theory of evolution by natural selection is now widely accepted. Data is now available to support the theory of evolution.
    - Fossils are the remains of organisms from millions of years ago, which are found in rocks.
      - Suggested Activity:
        Discuss how fossils provide evidence for evolution.
    - Extract and interpret information from charts, graphs and tables related to fossil evidence
    - Fossils may be formed:
      - from parts of organisms that have not decayed because one or more
      of the conditions needed for decay are absent
      - when parts of the organism are replaced by minerals as they decay
      - as preserved traces of organisms, such as footprints, burrows and
      rootlet traces.
      - Suggested Activity:
        Observe fossils or pictures of fossils.
        Model how a fossil can be formed.
    - Many early forms of life were soft-bodied, which means that they have left few traces behind.
    - What traces there were have been mainly destroyed by geological activity. This is why scientists cannot be certain about how life began on Earth.
    - We can learn from fossils how much or how little different organisms
      have changed as life developed on Earth.
    - Appreciate why the fossil record is incomplete
    - Understand how scientific
      methods and theories
      develop over time.
      - Suggested Activity:
        Consider theories of how life on Earth began.
    - Students should be able to extract and interpret information from charts, graphs and tables such as evolutionary trees
    - Extinctions occur when there are no remaining individuals of a species still alive.
      - Suggested Activity:
        Give a list of extinct organisms and ask students to print images. Suggest reasons to explain why they died out.
        Explain why some organisms are endangered. Give examples. Give reasons why it is important to prevent species from becoming extinct
    - Students should be able to describe factors which may contribute to the extinction of a species
      - Suggested Activity:
        Research causes of extinction and write a report/PowerPoint presentation to present to the class.
  - Lesson 10 - Why is MRSA so dangerous? Lesson Plan Lesson Title
    - Bacteria can evolve rapidly because they reproduce at a fast rate.
    - Stages of antibacterial resistance include: 1. Mutations of bacterial pathogens produce new strains. 2. Some strains might be resistant to antibiotics, and so are not killed. 3. They survive and reproduce, so the population of the resistant strain rises. 4. The resistant strain will then spread because people are not immune to it and there is no effective treatment.
      - Suggested Activity:
        Explain how bacteria can become resistant to antibiotics.
    - MRSA is resistant to antibiotics. There are links with this content to
      Antibiotics and painkillers.
      - Suggested Activity:
        Discuss how the rate of development of resistant bacteria could be slowed down.
        
        Discuss why there are few new antibiotics being developed, and suggest how drug companies might be encouraged to develop some.
    - To reduce the rate of development of antibiotic resistant strains:
      ? doctors should not prescribe antibiotics inappropriately, such as treating non-serious or viral infections
      ? patients should complete their course of antibiotics so all bacteria are killed and none survive to mutate and form resistant strains
      ? the agricultural use of antibiotics should be restricted.
      - Suggested Activity:
        Explain how antibiotic resistance has impacted on cleaning practices in Britain’s hospitals.
    - The development of new antibiotics is costly and slow. It is unlikely to keep up with the emergence of new resistant strains
      - Suggested Activity:
        Role play: life without antibiotics.