生物学SL试卷markscheme2005年11月.pdfVIP

Section B Extended response questions - quality of construction  Extended response questions for SL P2 carry a mark total of [20] . Of these marks, [18] are awarded for content and [2] for the quality of construction of the answer.  Two aspects are considered: expression of relevant ideas with clarity structure of the answers.  [1] quality mark is to be awarded when the candidate satisfies EACH of the following criteria. Thus [2] quality marks are awarded when a candidate satisfies BOTH criteria. Clarity of expression: The candidate has made a serious and full attempt to answer all parts of the question and the answers are expressed clearly enough to be understood with little or no re-reading. Structure of answer: The candidate has linked relevant ideas to form a logical sequence in at least two parts [(a), (b), etc.] of the question.  It is important to judge this on the overall answer, taking into account the answers to all parts of the question. Although, the part with the largest number of marks is likely to provide the most evidence.  Candidates that score very highly on the content marks need not necessarily automatically gain [2] marks for the quality of construction (and vice versa). SECTION A 1. (a) line 3 / line III [1] (b) (i) transgenic have more (%) starch than control; transgenic have less sugar than control; transgenic greater total amounts (% fresh weight) of carbohydrates than control; greater differenc ween (%) starch and (%) sugar in