4th Sep '25

Schemes of Work

B1
- B1.2
  - Lesson 01 - How do we replace old and damaged cells? Lesson Plan Lesson Title
    - The nucleus of a cell contains chromosomes made of DNA molecules.
    - Each chromosome carries a large number of genes.
    - In body cells the chromosomes are normally found in pairs.
      - Suggested Activity:
        Quiz pupils about their knowledge of DNA and chromosomes, testing keywords.
        GF: question as to why chromosomes exist in pairs.
    - Cells divide in a series of stages called the cell cycle.
    - Students should be able to describe the stages of the cell cycle, including mitosis.
    - During the cell cycle the genetic material is doubled and then divided into two identical cells.
    - Before a cell can divide it needs to grow and increase the number of sub-cellular structures such as ribosomes and mitochondria. The DNA replicates to form two copies of each chromosome.
      - Suggested Activity:
        Flow diagram of the stages of the cell cycle describing the key points of each stage. Have flow diagram cycle round.
    - In mitosis one set of chromosomes is pulled to each end of the cell and the nucleus divides.
    - Finally the cytoplasm and cell membranes divide to form two identical cells.
    - Students need to understand the three overall stages of the cell cycle but do not need to know the different phases of the mitosis stage.
    - Cell division by mitosis is important in the growth and development of multicellular organisms.
    - Students should be able to recognise and describe situations in given contexts where mitosis is occurring.
      - Suggested Activity:
        Stretch: Describe/Draw annotate what happens to the replicated chromosomes during mitosis.
        Challenge: Explain how mitosis makes sure that the division results in two genetically identical daughter cells.
        GF: Explain why it is important that cell division is a very controlled process.
  - Lesson 02 - What increases the risk of getting cancer? Lesson Plan Lesson Title
    - There are also genetic risk factors for some cancers.
    - Students should be able to describe cancer as the result of changes in cells that lead to uncontrolled growth and division.
      - Suggested Activity:
        Explore the treatments used for cancer, discuss how these work.
    - Benign tumours are growths of abnormal cells which are contained in one area, usually within a membrane.
    - Benign tumours do not invade other parts of the body.
    - Malignant tumour cells are cancers.
    - Malignant tumours invade neighbouring tissues and spread to different parts of the body in the blood where they form secondary tumours.
      - Suggested Activity:
        https://www.youtube.com/watch?v=OcigJn8UJNQ
        Describe the difference between malignant and benign tumours.
        Explain how cancers can spread to other parts of the body.
    - Scientists have identified lifestyle risk factors for various types of cancer.
      - Suggested Activity:
        Analyse data on biological and lifestyle factors linked to forms of cancer.
        GF/EW: Evaluate how well different factors can be limited to decrease the chance of getting cancer.
  - Lesson 03 - What are stem cells and how can we use them? Lesson Plan Lesson Title
    - Most types of animal cell differentiate at an early stage.
    - As an organism develops, cells differentiate to form different types of cells.
    - As a cell differentiates it acquires different sub-cellular structures to enable it to carry out a certain function. It has become a specialised cell.
    - Students should be able to explain the importance of cell differentiation.
    - In mature animals, cell division is mainly restricted to repair and replacement.
      - Suggested Activity:
        Stretch - recall why new cells need to be made
        Challenge - Explain why multicellular organisms are made of different types of cell?
    - A stem cell is an undifferentiated cell of an organism which is capable of giving rise to many more cells of the same type, and from which certain other cells can arise from differentiation.
    - Students should be able to describe the function of stem cells in embryos, in adult animals and in the meristems in plants.
    - Stem cells from human embryos can be cloned and made to differentiate into most different types of human cells.
    - Stem cells from adult bone marrow can form many types of cells including blood cells.
    - Knowledge and understanding of stem cell techniques are not required.
      - Suggested Activity:
        Double bubble stem cells and specialised cells.
    - Treatment with stem cells may be able to help conditions such as diabetes and paralysis.
    - In therapeutic cloning an embryo is produced with the same genes as the patient.
    - Stem cells from the embryo are not rejected by the patient?s body so they may be used for medical treatment.
    - The use of stem cells has potential risks such as transfer of viral infection, and some people have ethical or religious objections.
      - Suggested Activity:
        GF: Discuss the ethical issues surrounding the use of artificial embryonic stem cells in people
    - (WS) Evaluate the practical risks and benefits, as well as social and ethical issues, of the use of stem cells in medical research and treatments.
      - Suggested Activity:
        EW: Evaluate the practical risks and benefits, as well as social and ethical issues, of the use of stem cells in medical research and treatments.
  - Lesson 04 - How can we use meristem tissue? Lesson Plan Lesson Title
    - Meristem tissue in plants can differentiate into any type of plant cell, throughout the life of the plant.
      - Suggested Activity:
        THIS PRACTICAL IS FOR HIGHER CLASSES, as it requires strict aseptic technicques!!
    - Stem cells from meristems in plants can be used to produce clones of plants quickly and economically.
    - Stem cells from meristems in plants are used. Rare species can be cloned to protect from extinction.
      - Suggested Activity:
        Practical: Cauliflower Cloning - Tissue Culture and Micropropagation
        https://www.saps.org.uk/secondary/teaching-resources/706-cauliflower-cloning-tissue-culture-and-micropropagation
        PROBABLY BEST FOR HIGHER ABILITY AS REQUIRES ASEPTIC TECHNIQUE
        Equipment Required:
        HIGHER ONLY: CAULIFLOWER CLONING
        
        Each student/pair requires:
         'Diluvials' or small sterilised glass jars containing medium (MS, 20g/l sucrose, 2.5mg/l Kinetin, 0.032% SDICN – see media prep notes)
         White ceramic tiles / chopping board
         Forceps
         Scalpel
         0.5% Solution Sodium Dichloroisocyanurate (SDICN) in small glass jar with cap (for sterilising forceps)
         10ml 0.5% SDICN solution in Universal bottle (28ml glass bottle) with screw cap. (1 x 4g Milton tablet in 160ml DI water, 2 in 320ml, 4 in 640ml or 5 in 800ml - see media prep notes)
         Petri dish
         Safety glasses and disposable gloves
         Lab coat
        Students/pairs require access to:
         70% ethanol for wiping down surfaces
         paper towels
         Cauliflower curd (the white 'floret' part) cut into 10mm3 pieces. Curd should be taken from a fresh, whole cauliflower, not ready-prepared cauliflower pieces.
         Glass or plastic beaker for waste solutions
    - Crop plants with special features such as disease resistance can be cloned to produce large numbers of identical plants for farmers.
      - Suggested Activity:
        EW: Research the uses of meristem cells by humans.
        GF: Evaluate the use of cloned plants to selective breeding of plants.
        GF: You are now in charge of all scientific research funding in the UK, you have to select one programme to receive all the available money which would you select, human stem cells or meristems?
  - Lesson 05 - What is diffusion? Lesson Plan Lesson Title
    - Substances may move into and out of cells across the cell membranes via diffusion.
    - Some of the substances transported in and out of cells by diffusion are oxygen and carbon dioxide in gas exchange.
    - Some of the substances transported in and out of cells by diffusion are the waste product urea from cells into the blood plasma for excretion in the kidney.
    - Explain how the difference in concentrations (concentration gradient) affect the rate of diffusion.
    - Explain how the difference in the temperature affect the rate of diffusion.
    - Diffusion is the spreading out of the particles of any substance in solution, or particles of a gas, resulting in a net movement from an area of higher concentration to an area of lower concentration.
      - Suggested Activity:
        Activity 1:
        Dropping food colouring into beakers of water to see the diffusion. (could vary temperature of water to see how it affects the rate)
        
        Activity 2:
        Spraying perfume in corner of the room. Hands up when they can smell it.
        Equipment Required:
        Activity 1:
        food colouring pipettes
        250mL beakers
        thermometers
        kettles
        ice
        timers
        
        Activity 2:
        perfume spray
    - Explain how the surface area of the membrane affect the rate of diffusion.
      - Suggested Activity:
        Task 1: What factors could affect the rate of diffusion?
        Task 2: Draw sketch graphs for the different factors that can affect the rate of diffusion
        
        SUPER CHALLENGE:Explain, using examples from nature how factors can affect the rate of diffusion.
        CHALLENGE:Explain how each factor affects the rate of diffusion in terms of particles.
        STRETCH:Describe the factors that can affect the rate of diffusion in terms of particles.
  - Lesson 06 - How is osmosis different to diffusion? Lesson Plan Lesson Title
    - Osmosis is the diffusion of water from a dilute solution to a concentrated solution through a partially permeable membrane.
      - Suggested Activity:
        http://highered.mheducation.com/sites/0072495855/student_view0/chapter2/animation__how_osmosis_works.html
    - (WS) Recognise, draw and interpret diagrams that model osmosis.
      - Suggested Activity:
        A single layer of plant cells is placed on a microscope slide and either distilled water or 5% sodium chloride solution is added to the cells. Osmosis will occur resulting in either turgid cells or plasmolysed cells.
        
        http://www.nuffieldfoundation.org/practical-biology/observing-osmosis-plasmolysis-and-turgor-plant-cells
        Equipment Required:
        per group:
        Microscope
        Microscope slides, 1 per specimen
        Cover slips, 1 per specimen
        Distilled water
        Salt solution (sodium chloride) 5% w/v
        Teat pipettes
        Forceps
        Pieces of filter paper
        
        per class:
        Red onion, cut into slices approximately 1 cm wide, 1 or 2
        Alternatives:
        Rhubarb stem
        Ivy-leaved toadflax (Cymbalaria muralis)
        Cladophora (a filamentous alga)
        Video microscope (if available)
    - (MS) Students should be able to:
      ? use simple compound measures of rate of water uptake
    - ? use percentages
    - ? calculate percentage gain and loss of mass of plant tissue.
    - (MS) Students should be able to plot, draw and interpret appropriate graphs.
  - Lesson 07 - How does surface area affect transport? Lesson Plan Lesson Title
    - Water may move across cell membranes via osmosis.
      - Suggested Activity:
        Set up cubes of agar jelly and see how far liquid penetrates them by diffusion over five minutes. Calculate surface area to volume ratio for cubes of different sizes and consider the problems faced by large organisms.
        Equipment Required:
        Each Group:
        Beaker 100 cm3,
        Ruler,
        Stopclocks
        
        Agar cubes 2 cm x 2cm,
        Agar cubes 1 cm x 1 cm,
        Agar cubes 0.5 cm x 0.5 cm,
        Hydrochloric acid, 0.1 M,
        20ml cylinders
    - A single-celled organism has a relatively large surface area to volume ratio.
    - Having a large surface area to volume allows sufficient transport of molecules into and out of the cell to meet the needs of the organism.
    - Students should be able to calculate and compare surface area to volume ratios. (MS)
    - Students should be able to explain the need for exchange surfaces in terms of surface area to volume ratio.
    - Students should be able to explain why multicellular organisms have transport systems in terms of surface area to volume ration
    - Students should be able to explain how the small intestine and lungs in mammals are adapted for exchanging materials.
    - Students should be able to explain how the gills in fish are adapted for exchanging materials.
    - Students should be able to explain how the leaves in plants are adapted for exchanging materials.
    - In multicellular organisms, surfaces and organ systems are specialised for exchanging materials.
    - Specalised surfaces allow sufficient molecules to
      be transported into and out of cells for the organism?s needs.
      - Suggested Activity:
        Research adaptations lungs, gills and leaves, describing the chemicals exchanged with directions, adaptations these organs have to carry out the exchange and explain how these adaptations help to maximise the exchange.
    - The effectiveness of an exchange surface is increased by:
      ? having a large surface area
      ? a membrane that is thin, to provide a short diffusion path
      ? (in animals) having an efficient blood supply
      ? (in animals, for gaseous exchange) being ventilated.
      - Suggested Activity:
        Explain why larger organisms need increasingly more complex exchange surfaces.
  - Lesson 08 - How does active transport work? Lesson Plan Lesson Title
    - Active transport moves substances from a more dilute solution to a more concentrated solution (against a concentration gradient).
    - Active transport requires energy from respiration.
    - Active transport allows mineral ions to be absorbed into plant root hairs from very dilute solutions in the soil.
    - Plants require ions for healthy growth.
    - Active transport also allows sugar molecules to be absorbed from lower concentrations in the gut into the blood which has a higher sugar concentration.
      - Suggested Activity:
        Venn Diagram to sort conditions between diffusion, osmosis and active transport (passive, uses energy, against concentration gradient, across a membrane, movement of water et.c)
    - Sugar molecules are used for cell respiration.
      - Suggested Activity:
        Describe the exchange that takes place in the small intestine.
    - Students should be able to describe how substances are transported into and out of cells by diffusion, osmosis and active transport
      - Suggested Activity:
        Explain why villi cells need a high number of mitochondria / why so much active transport needs to take place in the small intestines.
    - students should be able to explain the differences between the three processes.
      - Suggested Activity:
        GF: Evaluate whether it is worth the small intestines using energy to actively transport sugar into the blood.
  - Lesson 09 - Required Practical - Osmosis Lesson Plan Lesson Title
    - To plan and carry out the first part of the osmosis in potato practical.
    - To collect data from the osmosis in potato practical, draw graphs and make conclusions.
  - Lesson 10 - Lesson Plan Lesson Title
    - Assessment
  - Lesson 11 - Lesson Plan Lesson Title
    - Reflection