Switching to AQA: OCR Science B and Additional Science B

Transcription

1 Switching to AQA: OCR Science B and Additional Science B If you re thinking of switching to our GCSE Combined Science: Trilogy specification from OCR GCSE Science B (J261) and OCR GCSE Additional Science B (J262) for teaching from September 2016, this resource will provide a helpful comparison of the subject content and assessment for each awarding body. It directly compares the Biology components of the current OCR specifications with the Biology components of the AQA GCSE Combined Science: Trilogy specification (8464). Comparison overview The two specifications are quite different in terms of content and organisation. AQA Our specification contains more detail on digestion, heart treatments, fertility, classification systems and deforestation. The content can be delivered in a variety of ways. Our scheme of work has suggestions for learning activities where students can develop their skills in practical work, working scientifically and mathematics. Our Biology and Combined Science: Trilogy specifications are designed to make co-teaching easier. OCR OCR s specification is set out for four exam papers and two internally-assessed controlled assessments. It has more detail on fitness and health, diet, the eye, classification of drugs, thermoregulation, plant hormones, arthropods, pyramids of biomass, nitrogen cycle, decay processes, fieldwork methods and sampling techniques, indicator species, biological control of pests, farming techniques, measuring growth, cloning, DNA and protein synthesis. Assessment Two externally-assessed written papers, marked by AQA. Each paper is 1 hour 15 minutes. Four written papers across the two specifications, on Biology, Chemistry and Physics, marked by OCR. Each

2 The Fundamental biological concepts and principles' section at the start of the specification highlights knowledge that could be examined in either paper. paper is 1 hour 15 minutes or 1 hour 30 minutes. One of the two papers from each specification includes a 10-mark section about analysis of evidence. Practicals Five compulsory practicals. The exam papers could also examine students on their practical skills. The required practicals are clearly listed, and we show opportunities for developing practical skills in the specification s right-hand column. These should encourage more practical work, motivate students and help you transfer skills across the subject. Questions based on the required practicals make up at least 15% of the total mark. Two controlled assessments on practical skills, marked by centres. Each module includes suggested practical and research activities. Controlled assessments make up 25% of the total mark. Content Overview The content is organised into seven topics: 1-4: Cell biology, Organisation, Infection and response, Bioenergetics (assessed in Paper 1). 5-7: Homeostasis and response, Inheritance, variation and evolution, Ecology (assessed in Paper 2). The content is organised into four modules: B1: Understanding Organisms B2: Understanding Our Environment B3: Living And Growing B4: It s A Green World

3 Working scientifically WS 1.1 to WS 4.6 The Working scientifically content takes in all the activities that scientists do. It appears throughout the whole specification and the written papers, and we crossreference activities. Fundamental Scientific Processes and Controlled assessment tasks (Internal assessment) The 'How Science Works' content is assessed across all the exam papers. Students need to understand fundamental principles that underpin the specification s scientific explanations. Cell biology Cell structure Both specifications cover plant, animal and bacterial cell structure, and cell specialisation to B1c, B3a, B3e, B3f More detail on cell structure, specialisation and differentiation. Comparison of light and electron microscopes. Calculations involving magnification, real size and image size. Eukaryotic and prokaryotic cells are compared. Microscopy is inferred in the content and suggested practical activities. Eukaryotic and prokaryotic cells are not mentioned.

4 4.1.2 Cell division Both specifications cover chromosome structure, mitosis and stem cells. The risks, benefits and ethical issues have to be considered in relation to the use of stem cells to B3a, B3f, B3d Stem cells in plants and animals. Therapeutic cloning and the uses of stem cells. Methods to measure growth. Growth curves for plants and animals Transport in cells Both specifications cover diffusion, osmosis and active transport, factors affecting the rate of diffusion, and the need for specialised exchange surfaces in multicellular organisms to B3d, B4d, B4f Factors affecting the effectiveness of exchanges surfaces. Effect of osmosis in animal cells and plant cells, and associated terminology. A required practical: investigate the effect of salt or sugar solutions on plant tissue. Similar suggested practicals: investigate diffusion and osmosis. Active transport is linked to mineral ion absorption and absorption of sugar from the gut. Only active transport in plant roots. Organisation Principles of organization Organisation is present in both specifications.

5 B3d, B3e Definitions of cells, tissues and organs. Advantages and implications of becoming multicellular. Organisation is implicit in the description of the circulatory system Animal tissues, organs and organ systems Our specification covers a range of topics, including digestive system and enzyme activity, the heart and circulatory system, non-communicable diseases such as CHD, Type 2 diabetes, cancer, some lung and liver diseases and their associated risk factors. Both specifications cover properties of enzymes and an understanding of the 'lock and key theory', including the investigation of enzyme activity. Both specifications are similar in the way they cover the structure and functions of the heart, blood vessels and the blood. Risk factors for heart disease are covered by both. Both specifications cover the effects of smoking and alcohol, the link between obesity and Type 2 diabetes to B1a to B1c, B3b, B3e Knowledge of the digestive system from Key Stage 3, and the action of digestive enzymes, including the role of bile. A required practical: investigate the effect of a factor on the rate of an enzyme-controlled reaction. Digestive system and digestion are not covered. A similar practical is suggested. Calculate Q10 value for a given reaction.

6 to B1a to B1c, B3b, B3e Nutrition, balanced diets and major food groups. Detail on impacts of malnutrition and overeating. Calculate Estimated Average Daily Requirement (EAR) and Body Mass Index (BMI). The relationship between the heart and lungs, and the role of coronary arteries. Much more focus on heart disease and treatments, including pacemakers, stents, valves, artificial hearts, transplants and drugs. Names of heart valves must be learnt Detail on blood pressure. Lungs, coronary arteries, and treatments for heart diseases are not covered. The difference between fitness and health. Measuring fitness. Factors affecting mental health. Only risk factors for cancer. Cancers and how they spread in the body Plant tissues, organs and systems Both specifications cover: The role of meristems. Leaf structure, including the names and functions of tissues. The structure of xylem and phloem, and the term translocation.

7 Factors affecting the rate of transpiration and the role of stomata and guard cells to control gas exchange and water loss. There are several investigations and activities to develop skills in relation to transpiration to B4c, B4d, B4e Infection and response Communicable diseases Viruses, bacteria and fungi can cause infectious diseases. Both specifications cover: How the body defends itself against the entry of pathogens. Immunity and vaccinations. The use of antibiotics and the development of antibiotic resistant organisms. The testing of new drugs, including double-blind trials and placebos to , , B1c, B1e A definition of pathogen, and the causes, transmission, symptoms and prevention or treatment of several viral, bacterial, fungal and protist diseases of humans and plants. These include: measles, HIV, tobacco mosaic virus, salmonella, gonorrhoea, rose black spot and malaria. Specific diseases include cholera, food poisoning, influenza, athlete s foot and malaria. Plant diseases are not covered, other than the symptoms of nitrate, phosphate, potassium and magnesium ion deficiencies. The use of nitrate ions to produce amino acids and proteins. Methods to reduce the

8 to , , B1c, B1e spread of diseases. Antitoxins are produced by white blood cells. Painkillers and drugs extracted from plants. Detail on antibiotic resistance, including how resistant strains evolve and how to reduce the rate at which they develop. The difference between antibiotics and antiviral drugs. Classification of drugs, with examples. The effects of alcohol and smoking. The work of Fleming. Bioenergetics Photosynthesis Both specifications cover the word and symbol equations for photosynthesis, the use of glucose produced by photosynthesis, factors affecting and limiting the rate of photosynthesis and the interpretation of related data. There is a required practical in the AQA specification about the effect of a factor on the rate of photosynthesis. A similar investigation is suggested in the OCR specification to B4b, B4f Photosynthesis is an endothermic reaction. Photosynthesis is a two-stage process. How an understanding of

9 to B4b, B4f photosynthesis was developed over time, including the use of isotopes. Factors affecting the rate of photosynthesis also include the amount of chlorophyll. Inverse square law not covered. Use of the inverse square law in relation to light intensity. The economics of enhancing conditions in a greenhouse while maintaining a profit. Greenhouse economics is inferred in a suggested research activity. The use of nitrate ions to produce amino acids and proteins. The use of mineral ions and the symptoms of deficiency diseases Respiration The use of energy in organisms. Aerobic and anaerobic respirations are compared. Word and symbol equations are included for aerobic respiration, and the word equations for anaerobic respiration in animals. Investigating the effect of exercise on the body. The section on exercise also includes reference to lactic acid build up and breakdown of lactic acid in the liver, oxygen debt and muscle fatigue to B3c, B4b

10 to B3c, B4b Respiration is an exothermic reaction. Word and symbol equation for anaerobic respiration in yeast and plants. Lactic acid build up, breakdown of lactic acid in the liver, oxygen debt and muscle fatigue. Measuring the rate of respiration. Effect of ph and temperature on the rate of respiration. Respiratory quotient calculations. ATP as an energy source. Anaerobic respiration in plants in waterlogged soil, and bacteria in puncture wounds. The effect of exercise on blood pressure and recovery rate. Summary of metabolism (covered in more detail in , and ) Homeostasis and response Homeostasis Both specifications define the term homeostasis, and refer to blood glucose regulation and body temperature regulation. (Control of blood glucose is covered in detail in section of our specification.) Automatic control systems are described in terms of receptors, coordination centres and effectors. Nervous and chemical examples are given B1f

11 4.5.2 The human nervous system Both specifications cover the structure and functions of the nervous system, including reflex arc, and include investigations into reaction time B1d, B1e A required practical: investigate the effect of a factor on human reaction time. More detail about the structure of neurons, including the terms axon, cell body, and fatty sheath. The eye is not covered. The structure of the eye. The advantages and disadvantages of monocular and binocular vision. Eye defects, including long and short-sightedness and how these can be corrected, as well as colour blindness. Drugs and the effect of drugs on the nervous system, including modes of action at the synapse. Beneficial and harmful use of drugs Hormonal coordination in humans There is similar coverage of control of blood glucose levels, Type 1 and Type 2 diabetes including their causes, treatments and risk factors to B1f, B1g A definition of the term hormone, and the position of endocrine glands in the body.

12 to B1f, B1g Detail on thermoregulation. The development of secondary sexual characteristics and hormonal control of the menstrual cycle. Fertility is not covered. Hormonal and nonhormonal methods of contraception, and the use of hormones in IVF treatment. The negative aspects of fertility treatment are considered. The roles of adrenaline and thyroxine as negative feedback systems. Plant hormones are not covered. Refers to negative feedback mechanisms in general terms. Phototropism and geotropism in relation to auxin. The uses of plant hormones in selective weed killers, rooting powder, fruit ripening and control of dormancy. Inheritance, variation and evolution Reproduction Descriptions of mitosis and meiosis are covered in relation to gamete formation, the restoration of the normal number of chromosomes at fertilisation and formation of an embryo. Genetic inheritance is covered in a similar way, including the terminology associated with genetic crosses. Both specifications require outcomes of crosses to be analysed and calculations made. Inherited disorders are considered. Sex determination is covered in both specifications.

13 The structure of DNA as a double helix. A gene codes for a specific protein to B1h, B3a, B3b, B3d, B3h Sexual and asexual reproduction are described and compared in terms of their advantages. Asexual reproduction is only mentioned in terms of cloning. Some organisms that can use both sexual and asexual reproduction. Base pairings and how the DNA base sequence determines the amino acid sequence. The functions of some proteins. The work of Watson and Crick. The importance of the human genome in linking genes to particular diseases, treatment of inherited disorders and tracing migration patterns. Inherited disorders: polydactyl and cystic fibrosis. Ethical issues concerning embryo screening. DNA sequencing as a tool in taxonomy. Inherited disorders: red-green colour blindness, sickle cell anaemia and cystic fibrosis Variation and evolution Genetic and environmental variation, including the effect of mutations. Darwin's theory of evolution by natural selection and the advantages and disadvantages of selective breeding. There is a brief reference to speciation in both specifications. Examples of genetic engineering and the advantages and disadvantages of the process.

14 to , B1h, B2f, B3g, B3h Genetic engineering examples include disease, pest and pesticide resistance in plants, human insulin production, and research exploring the use of genetic modification to overcome some inherited diseases. Genetic engineering examples include herbicide, frost and disease resistant crops, beta carotene production in rice, and human insulin production. Cloning of stem cells to treat diabetes and paralysis and therapeutic cloning, but not in detail. Adult cell cloning is described but not named. Tissue culture and cuttings as examples of cloning in plants. Identical twins are natural clones. The benefits and risks of cloning The development and understanding of genetics and evolution Darwin's theory of evolution by natural selection and evidence for evolution, including the fossil record. The causes of extinction to B2f, B2h Lamarck s theory of evolution. Evidence for evolution includes genetic inheritance, the fossil record and antibiotic resistant bacteria. How fossils may be formed.

15 to B2f, B2h The development of strains of bacteria that are resistant to antibiotics. Not covered: how we could reduce rate of development of bacteria, and why we do not have antibiotics to treat them Classification of living organisms Organisms can be classified into groups based on their physical features and DNA. Organisms are classified into smaller and smaller groups, from kingdoms to species. Organisms are named by the binomial system of genus and species. How evolutionary trees are used to show how organisms are related. Some development of ideas around modern techniques for classification including DNA sequencing B2a Much more focus on why and how new models of classification have been developed due to improvements in microscopes and chemical analysis. DNA sequencing is the only modern technique covered. The Linnaean system classifies organisms into: kingdom, phylum, class, order, family, genus and species. Includes the Linnaean system, but not Woese. A definition of the term species. The three-domain system

16 B2a developed by Woese. Ecology Adaptations, interdependence and competition Organisms have structural, behavioural and functional adaptations to survive in their habitats. The interdependence of organisms. Competition for resources. A wide range of terms related to ecology are used to B2d to B2f, B4a The effect on communities of changes in biotic and abiotic factors. Extremophiles are adapted to survive high temperature, pressure or salt concentration. Some adaptations of extremophiles are given. Definition of a stable community. Examples of interdependence include parasitism and mutualism Organisation of an ecosystem Feeding relationships. The use of quadrats to estimate a plant population size.

17 Interpreting predator-prey cycles. The carbon cycle to B2b, B2c, B2d, B4a, B4g A required practical: investigate the population size of a common species in a habitat. Measurement of environmental factors and a variety of fieldwork techniques. Estimating population size using capture-recapture data. Using maps and kite diagrams. Pyramids of number and biomass. The water cycle. Decay only covered in relation to returning carbon to the atmosphere and mineral ions to the soil. The nitrogen cycle. Detail on the decay process, including how it s related to compost heaps and food preservation techniques Biodiversity and the effect of human interaction on ecosystems The importance of maintaining biodiversity for future generations. The problems associated with an increasing human population. Sustainable development can be improved by reducing pollution and conserving resources to B2g, B2h, B4a, B4h

18 to B2g, B2h, B4a, B4h Environmental change can be measured using living and non-living indicators. Mainly focuses on the effect of an increasing population on waste management, in order to reduce pollution from a range of sources. Land use and maintaining peat bogs and other habitats. Deforestation and global warming, including how they impact biodiversity. Programmes to maintain biodiversity. Detail on sustainability and protecting ecosystems, with a focus on conservation using a case study of whale conservation. Compare the biodiversity of natural and artificial ecosystems. A comparison of organic and intensive farming techniques. Hydroponics, fish farming, battery farming, greenhouses and crop rotation. Links made between intensive farming methods and efficiency of energy transfer in food chains. Reducing energy losses due to predation, competition, pest damage, for movement and to keep warm. Biological control of pests.