WJEC Biology for AS Level Student Book: 2nd Edition

Species Number of stomata / cm -2 Upper (adaxial) surface Lower (abaxial) surface Apple 0 29400 Maize 2500 2300 This is an AO3 question because it asks you to draw a conclusion about the relative rates of transpiration from the two sides of leaves and to draw a conclusion from the data. AO3 develop and refine practical design and procedures The image shows the scarlet pimpernel, Anagallis arvensis . It is a small herbaceous plant that may be found in meadows. The scarlet pimpernel In a study designed to compare the number of scarlet pimpernels in a field with clay soil with the number in a field with sandy soil, ten 0.25 m 2 quadrats were placed randomly in a 10m × 10m grid in each field, and the number of quadrats containing the scarlet pimpernel was counted. Suggest two ways in which the validity of the comparison could be increased. [2] This question is AO3 because asking for a method to increase the validity of the experiment is asking you how to refine the experimental design. Examinations Two units will be examined at AS Level. The examinations will each last 1 hour 30 minutes and comprise short-answer questions, longer, structured questions and one question requiring an answer in extended prose. All questions will be compulsory and the papers will each offer a total of 80 marks. The assessment is summarised in the table below: Level Exam Time Marks AS Unit 1 1h 30 80 Unit 2 1h 30 80 Examination questions ▪ As well as being able to recall biological facts, name structures and describe their functions, you need to appreciate the underlying principles of the subject and understand associated concepts and ideas. In other words, you need to develop skills so that you can apply what you have learned, perhaps to situations not previously encountered. ▪ You may be asked to inter-convert numerical data and graph form, analyse and evaluate numerical data or written biological information, interpret data and explain experimental results. These mathematical questions account for a minimum of 10% of the total marks. ▪ Practical work is an essential part of biology and you will undertake practical tasks throughout your course. Your practical knowledge and understanding are assessed in written examinations, where they represent a minimum of 15% of the total marks. You will be expected to answer different styles of question, for example: ▪ Short-answer questions – these often require a brief answer such as the name of a structure and its function, for one mark, or a simple calculation. ▪ Structured questions – these may be in several parts, usually about a common theme. They become more difficult as you work your way through. Structured questions can be short, requiring a brief response, or may include the opportunity for extended writing. The number of lined spaces and the mark allocation at the end of each part question are there to help you. They indicate the length of answer expected. If three marks are allocated then you must give at least three separate points. ▪ Extended prose questions – examination papers will contain one question, worth nine marks, which requires extended prose for its answer. This is not an essay and so does not require the structure of introduction – body – conclusion. Often candidates rush into such questions. You should take time to read the question carefully, to discover exactly what the examiner requires in the answer, and then construct Introduction 9