Core Science Module 1 : 9 th January Module 2 : 17 th January Module 3 : 23 rd May Triples _____________ No exams until summer 2014 Controlled assessment 25% of award

Summer 2013

Username : parent.yr10 Password : science Username : firstname.lastname Password : science

Revision and Online Assessments Online assessments Past papers

The Return of the Extended answer 18 marks out of 60 for each paper. (3x 6 mark questions). 3 papers per qualification.

OXBOX

Module P2 Upgrade: Model answers 4 © Oxford University Press 2011 Ozone Foundation tier question Click anywhere on this screen to proceed. Navigate using the links at the bottom of every screen.

© Oxford University Press 2011 Module P2 Upgrade: Model answers 4 Question Explanation of question Answer Question The Sun gives off radiation which then reaches the Earth. Some of this radiation is very dangerous to living organisms, including humans, but a chemical found high in the atmosphere protects us from it Explain why this radiation is dangerous and describe the process by which the chemical in the atmosphere protects us. Make sure that you use correct scientific terms in your answer. [4]

© Oxford University Press 2011 Module P2 Upgrade: Model answers 4 Question Explanation of question Answer Explanation of question This is a free response question worth four marks. You need to recall and explain that ultraviolet radiation from the Sun is absorbed by ozone in the atmosphere, and that ultraviolet is ionising and causes damage to living cells. There are four marks available which suggests that you should make four distinct points.

© Oxford University Press 2011 Module P2 Upgrade: Model answers 4 Question Explanation of question Answer G–E answer The light from the sun includes dangerous radiation, and it is absorbed by the greenhouse gases. comment This candidate is confused between greenhouse effect and the ozone layer. However, one mark is awarded here for the word ‘absorbs’, even though ozone is not mentioned. Ozone is, in fact, a greenhouse gas, but does not contribute significantly to greenhouse effect. NextPrevious.

© Oxford University Press 2011 Module P2 Upgrade: Model answers 4 Question Explanation of question Answer D–C answer Ultra violet from the Sun is dangerous, because it can give you skin cancer. It does this by ionising DNA in your skin cells. It is blocked by the ozone like this: comment This candidate gets marks for using the terms ‘ultraviolet’ and ‘ozone’. Another mark is awarded for stating that ozone ‘blocks’ radiation, although it is much better to use the word ‘absorbs’. This idea is backed up by the diagram. The candidate gains a fourth mark for stating that radiation damages living cells and is ionising. NextPrevious.

© Oxford University Press 2011 Module P2 Upgrade: Model answers 4 Question Explanation of question Answer D–C answer (continued) comment The candidate has gained full marks, even though ‘ionising DNA’ is a mixture of two ideas rather than a coherent explanation. The diagram alone would have been enough to gain the ozone and ultraviolet marks. NextPrevious.

Module P2 Upgrade: Model answers 5 © Oxford University Press 2011 Global warming Higher tier question Click anywhere on this screen to proceed. Navigate using the links at the bottom of every screen.

© Oxford University Press 2011 Module P2 Upgrade: Model answers 5 Question Explanation of question Answer Question (part 1) The graph shows how the average temperature of the Earth’s surface has changed over the past 150 years. The data is the temperature difference from the mean value of temperature during between the years 1850 and This value is referred to as the ‘previous mean’.

© Oxford University Press 2011 Module P2 Upgrade: Model answers 5 Question Explanation of question Answer Question (part 2)

© Oxford University Press 2011 Module P2 Upgrade: Model answers 5 Question Explanation of question Answer Explanation of question (part 1) This question is linked to what you know about the warming of the earth. However, it is mainly testing your ability to analyse evidence and interpret information from graphs. The first step is to read the ‘stem’ (the instructions above the graph) and to look carefully at what the graph axes are telling you. In (a) the information from the graph must be interpreted and communicated. There are three marking points. To get two marks, all three must be present. Two must be present for one mark.

© Oxford University Press 2011 Module P2 Upgrade: Model answers 5 Question Explanation of question Answer D–C answer (a)Between 1850 and about 1923 it went up and down, but from 1923 on it started to go up, but not at a steady rate, and it even went down between 1940 and 1950, and down a bit about 1970 too, but after that it went up and up. comment This response is worth two marks. The candidate has concentrated on describing in detail but the ‘big picture’ is also clear. The idea of fluctuation is conveyed in the phrase ‘went up and down’. The phrase ‘from 1923 on it started to go up’ covers both that the graph is initially constant and the rising trend more recently. NextPrevious.

© Oxford University Press 2011 Module P2 Upgrade: Model answers 5 Question Explanation of question Answer B–A* answer (a)The graph has a lot of random variation, but it didn’t show any real trend until after 1970, when it has been going up all the time. comment This response is worth two marks. The candidate conveys the idea of fluctuation without any trend in the first sentence. The increase is described in the second sentence. NextPrevious.