[Pearson Edexcel]
[Always Learning]
Hi I'm Frankie. I am the Assistant Principle Examiner for Science GCSE. I mark a lot of
papers and I am here today to talk to the Science team about how we can help candidates
in the future.
[Mini Walking Talking Mocks - Pearson Edexcel GCSE (9-1) Science]
As you know practical skills are assessed in the examination now. About
15% of the marks are on practical skills. They might be on the core practicalís that
you are familiar with, but they also might be on the skills, apparatus and techniques
that youíve learnt in those core practical in a slightly different context.
So, these questions can test any of the assessment objectives. If you are asked to write a plan
from a core a practical that you are familiar with then that would be AO1, but you might
be asked use a technique or piece of apparatus from a core practical in a different context,
that would be AO2 applying your knowledge. Also, they might give you a method or set
of results and you might be asked to evaluate or improve that, and that would be AO3. So,
Iíve got some exam questions here that we can look at along with some exemplar answers
so why donít we do that now?
The first question is 4ci from the Biology foundation paper 2.
This question is based on a core practical 9.5. The question is about sampling glow-worms.
It is very likely that students did not sample glow-worms. However, they should have carried
out sampling methods including use of quadrats. When answering any question, it is important
to stop and think, what is this question about? This question is not about glow-worms. It
is about sampling techniques. So, this question covers AO1 and 2. It tests knowledge of sampling
which is AO1 and asks candidates to apply it in an unfamiliar context which is AO2.
The word 'mean' is in bold because the candidate needs to describe how to work out the mean
in order to answer this question. So, the question is not just asking how to take a
sample but how to use the data from a sample. The command word is 'Describe'. Describe is
a little bit like telling a story. The ideas should flow, and they should be linked but
there is no need to explain or justify any part of your answer. Think about it like writing
a recipe. It is a series of steps that should go in the correct order. Otherwise it won't
work. There are 3 marks for this question and that
means candidates need to write three things to get all the marks.
Why don't you pause the video now and have a go at this question?
Here is the mark scheme for 4 c i. There are 3 marks available, but the candidate
can write any 3 of 5 points to gain the mark. Words that are underlined must be used to
gain that mark point. So, to gain the first mark point you have to write quadrat. You
can't describe what a quadrat is or use another word. Make sure you can confidently name scientific
equipment which is used for practical investigations. Here it was necessary to use the correct scientific
term, quadrat, to get marking point one. For practical investigations, knowing and using
the terms for equipment is important and can help you pick up more marks than just a vague
description.
Words in brackets like female on the mark scheme do not need to be there but it must
be clear from your answer that you are talking about the right thing. So, you don't need
the word female to get the third marking point but you can't state 'all glow-worms' or 'male
glow-worms' as this would be the wrong sample. Words in bold also do not need to be there.
Alternative words can be used. So, for example 'tally the amount' would be ok for the mark.
Here is an example of a 3-mark answer. So, if you have a look at this, put a quadrat,
that word quadrat gets you marking point 1 so that's the first mark. Putting that quadrat
into different areas will give them marking point 2. If you can see on the mark scheme
it says random placement and that's enough for put it into different areas. When it says
divide the number of glow-worms you recorded by the number of areas you placed quadrats
in. That's mark point 5 which it total number found divided by total number of samples.
You don't always need to use the exact words that you will see on a mark scheme.
The next question is about how to use a microscope effectively which is something you should
be able to do. However, this is an AO3 question which means that you have to analyse the information
and develop that, possibly with giving some improvement.
This question is based on a core practical 1.6. The command word here is 'explain'. This
means that there must be a justification of points made.
There are 4 marks available. Which means that you would be expected to give 2 improvements,
each worth a mark, and justify or explain each improvement, and each justification is
also worth a mark. There are several ways this method can be
improved but you can only gain 2 marks for improvements in this question, the other two
marks must be for explanations of those improvements. The explanations should be correctly linked
to the improvement to gain the explanation marks.
Again, it is important to stop and think, what is this question about? It is about the
method of using a light microscope. Therefore, there would be no marks for suggesting using
an electron microscope here as this changes the method to a different method rather than
improve the method being used. This is a very fine distinction to make. A question that
asks for suggestions of other methods or apparatus to be used to see onion cells would credit
use of electron microscopes. An 'explain' question will usually require
a statement followed by a reasoned justification to extend the statement. Use this structure
as a basis for your answers to this type of 'explain' question. The 1 and the 2 on the
answer lines will help you.
You may want to stop the video now to have a go at this question. Just remember, what
does the command word want you to do? Here is the mark scheme for 4a. As you can
see there are 5 linked pairs, but you only have to write any 2 of those 5 linked pairs
to gain the marks. If you only wrote the first point from each linked pair the most marks
they could gain is 2, even if you wrote all five. There must be the linked justifications
for the other two marks. This mark scheme has information in the additional
guidance column. This shows the examiner other words or ideas that they could accept. The
answers under the answer column are the answers we are looking for and what we expect you
to know. If there is a forward slash between words or ideas, for example where it says
'single / thin' this means that either is acceptable but if both are written they will
only get one mark as they are the same mark point.
So, remember with a question like this you need to give two improvements and two explanations
that are linked just like this candidate has. You can see they have given two improvements
the first one, put a stain, that's MP1 from the mark scheme. Putting that stain on the
onion so that it is easier to see different parts of the cell, will get them mark point
2. The second improvement is move the mirror and that's the improvement from mark point
9 and then to get more light in so that you can see the cells clearly is the justification
from mark point 10. This question is about understanding how a
Liebig condenser, so this is apparatus that you should know. Its an AO1 and an AO2 question
which means you need to recall how to use it and then apply that knowledge.
This question asks you to use arrows to show the flow of water. It is a good idea to trace
the water flow you have drawn to make sure it can flow that way. Many candidates drew
arrows that implied the water could flow through glass. This is obviously wrong.
There is only 1 mark here, however, the question asks for arrows (plural) so you must draw
more than one arrow to get the mark. It asks for flow in and flow out, so it is clear 2
arrows are needed. You may want to pause the video for a few
minutes to attempt this question
Here is the mark scheme for 4bi. The mark scheme does not specify the number
of arrows, but it must be clear that the water goes in at the bottom and leaves at the top.
This looks like an easy question, but many candidates got it wrong because they had not
considered how a condenser is used. Here is an example of a 1-mark answer.
The arrows drawn show water going in the condenser in the bottom and out the condenser at the
top so gain a mark. So, if we think about some of the things we've
talked about today, some of the key ideas, the first thing to do is when you read a question
stop and think, what is this question about. What is the Science, what is concept, is it
about apparatus and techniques? It may not be a context that you are familiar with, but
you will know the answer. Secondly is think about what style of question it is, is it
just basic recall or are you having to apply that knowledge or are you have to evaluate
or improve something. They will also tell you how many marks are on the question, so
if it is three marks you need three specific points to get all of those marks. And lastly
what is the command word? The command really does tell you how to answer that question.
Ok I'd better go and meet the team now, and share this information with them, but don't
forget we have got a website and there's plenty of information on there so look at the Science
GCSE Edexcel Website, there's past papers and there's guidance documents all of which
can help you.