Unit 3 - science / biology higher tier

General Certificate of Secondary Education
Biology 4411

BLY3H
Unit 3 Biology
Mark Scheme
2008 examination – January series

Mark schemes are prepared by the Principal Examiner and considered, together with the relevant questions, by a panel of subject teachers. This mark scheme includes any amendments made at the standardisation meeting attended by all examiners and is the scheme which was used by them in this examination. The standardisation meeting ensures that the mark scheme covers the candidates’ responses to questions and that every examiner understands and applies it in the same correct way. As preparation for the standardisation meeting each examiner analyses a number of candidates’ scripts: alternative answers not already covered by the mark scheme are discussed at the meeting and legislated for. If, after this meeting, examiners encounter unusual answers which have not been discussed at the meeting they are required to refer these to the Principal Examiner. It must be stressed that a mark scheme is a working document, in many cases further developed and expanded on the basis of candidates’ reactions to a particular paper. Assumptions about future mark schemes on the basis of one year’s document should be avoided; whilst the guiding principles of assessment remain constant, details will change, depending on the content of a particular examination paper. Further copies of this Mark Scheme are available to download from the AQA Website: www.aqa.org.uk Copyright 2008 AQA and its licensors. All rights reserved. COPYRIGHT AQA retains the copyright on all its publications. However, registered centres for AQA are permitted to copy material from this booklet for their own internal use, with the following important exception: AQA cannot give permission to centres to photocopy any material that is acknowledged to a third party even for internal use within the centre. Set and published by the Assessment and Qualifications Alliance. The Assessment and Qualifications Al iance (AQA) is a company limited by guarantee registered in England and Wales (company number 3644723) and a registered charity (registered charity number 1073334). Registered address: AQA, Devas Street, Manchester M15 6EX Dr Michael Cresswell Director General Biology BLY3H – AQA GCSE Mark Scheme 2008 January Series MARK SCHEME
Information to Examiners

1. General
The mark scheme for each question shows: • the marks available for each part of the question • the total marks available for the question • the typical answer or answers which are expected • extra information to help the Examiner make his or her judgement and help to delineate what is acceptable or not worthy of credit or, in discursive answers, to give an overview of the area in which a mark or marks may be awarded. The extra information is aligned to the appropriate answer in the left-hand part of the mark scheme and should only be applied to that item in the mark scheme. At the beginning of a part of a question a reminder may be given, for example: where consequential marking needs to be considered in a calculation; or the answer may be on the diagram or at a different place on the script. In general the right hand side of the mark scheme is there to provide those extra details which confuse the main part of the mark scheme yet may be helpful in ensuring that marking is straightforward and consistent. Emboldening
In a list of acceptable answers where more than one mark is available ‘any two
from’ is used, with the number of marks emboldened. Each of the following lines
is a potential mark.
A bold and is used to indicate that both parts of the answer are required to award
the mark.
Alternative answers acceptable for a mark are indicated by the use of or.
(Different terms in the mark scheme are shown by a / ; eg allow smooth / free
movement.)

3. Marking
3.1 Marking
This applies to questions requiring a set number of responses, but for which candidates have provided extra responses. The general principle to be followed in such a situation is that ‘right + wrong = wrong’. Each error/contradiction negates each correct response. So, if the number of error/contradictions equals or exceeds the number of marks available for the question, no marks can be awarded. However, responses considered to be neutral (indicated as * in example 1) are not penalised. Biology BLY3H – AQA GCSE Mark Scheme 2008 January Series Example 1: What is the pH of an acidic solution? (1 mark) Candidate Response Marks
Example 2: Name two planets in the solar system. (2 marks) Candidate Response
Use of chemical symbols / formulae
If a candidate writes a chemical symbol / formula instead of a required chemical name, full credit can be given if the symbol / formula is correct and if, in the context of the question, such action is appropriate. Marking procedure for calculations
Full marks can be given for a correct numerical answer, as shown in the column ‘answers’, without any working shown. However if the answer is incorrect, mark(s) can be gained by correct substitution / working and this is shown in the ‘extra information’ column; Interpretation of ‘it’
Answers using the word ‘it’ should be given credit only if it is clear that the ‘it’ refers to the correct subject. Errors carried forward
Any error in the answers to a structured question should be penalised once only. Papers should be constructed in such a way that the number of times errors can be carried forward are kept to a minimum. Allowances for errors carried forward are most likely to be restricted to calculation questions and should be shown by the abbreviation e.c.f. in the marking scheme. 3.6 Phonetic
spelling
The phonetic spelling of correct scientific terminology should be credited unless
there is a possible confusion with another technical term.
3.7 Brackets
(….) are used to indicate information which is not essential for the mark to be awarded but is included to help the examiner identify the sense of the answer required. Unexpected Correct Answers not in the Mark Scheme
The Examiner should use professional judgement to award credit where a candidate has given an unexpected correct answer which is not covered by the mark scheme. The Examiner should consult with the Team Leader to confirm the judgement. The Team Leader should pass this answer on to the Principal Examiner with a view to informing all examiners. Biology BLY3H – AQA GCSE Mark Scheme 2008 January Series BLY3H
Question 1
question answers
information
but no answer / wrong answer gains 1
mark
or wrong figures from graph
subtracted and divided by 10 gains 1
mark
or answer 0.61 gains 1 mark
or no ethanol / alcohol
Biology BLY3H – AQA GCSE Mark Scheme 2008 January Series BLY3H

Question 2

question answers
information
or to sterilise
or suitable / best for enzymes
allow grow / culture (at room temperature) ignore not killed / live or microorganisms / bacteria etc
eg ‘life from life’ or reference to
in gains 2 marks
Biology BLY3H – AQA GCSE Mark Scheme 2008 January Series BLY3H
Question 3

question answers
information
any two from:
• gets (free) fuel or cheap supply of
energy or (free) cooking / heating /
lighting
lower temperature or not enough heat
process is slower or enzymes action
Biology BLY3H – AQA GCSE Mark Scheme 2008 January Series BLY3H
Question 4

question answers
information
any three from:
• then more slowly (during exercise) accept rate (of increase) slows down • to max 126 / at 5 minutes / end of • rapid fall (during recovery) or use
any four from:
do not accept energy produced
muscles using more energy or
or to prevent anaerobic respiration
Biology BLY3H – AQA GCSE Mark Scheme 2008 January Series BLY3H

Question 5

question answers
information
any three from:
• glucose is filtered out of the blood allow absorbed into the blood but not
are large (molecules) or because
continued…
Biology BLY3H – AQA GCSE Mark Scheme 2008 January Series
Question 5 continued…

question answers
information
up to any three from:
restricted fluid intake or time
disadvantages: at least one from:
at least one disadvantage for full marks Biology BLY3H – AQA GCSE Mark Scheme 2008 January Series BLY3H
Question 6

question answers
information
any two from:
• uses energy • use of protein / carrier mitochondria – release energy or make do not accept ‘makes energy’
Biology BLY3H – AQA GCSE Mark Scheme 2008 January Series BLY3H
Question 7

question answers
information
ref. access of fungus to reactants / food / oxygen
or
maintain even temperature throughout
or
prevents sedimentation of fungus
any two from:
ignore ‘to cool’ – needs qualification do not allow death of enzymes or
heat / energy
or respiration releases / produces
heat / energy
continued…
Biology BLY3H – AQA GCSE Mark Scheme 2008 January Series BLY3H
Question 7 continued…

question answers
information
not just ‘used for growth’
of energy for Cephalosporium or
Cephalosporium (so Cephalosporium
must be present to produce it) or
Cephalosporium not produced until
growth has ceased

Source: http://www.uccrevision.co.uk/b3h_mark_scheme_jan_08.pdf