regional network meetings spring...
TRANSCRIPT
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Regional network meetings – spring 2016 OCR GCE Biology A (H020/H420)
OCR GCE Biology B (Advancing Biology) (H022/H422)
Biology A (H020/H420) website: http://ocr.org.uk/qualifications/as-a-level-gce-biology-a-h020-h420-from-2015/ Biology B (Advancing Biology) (H022/H422) website: http://ocr.org.uk/qualifications/as-a-level-gce-biology-b-advancing-biology-h022-h422-from-2015/ For more information on the OCR Science qualifications: - follow us on twitter: @ocr_science - check out our science homepage: http://www.ocr.org.uk/qualifications/by-subject/science/ - join our community: http://www.ocr.org.uk/community/ - find out about the Practical Endorsement: http://www.ocr.org.uk/positiveaboutpractical
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1 Contents
1 New, updated and moved topics 3
2 Multiple Choice Questions (MCQs) 6
3 Maths 7
4 Practical 8
5 Level of Response (LoR) 11
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1 New, updated and moved content
Biology A Specification Content: The Headlines
Change Topic Previous spec ref New spec ref
New Gaseous exchange in bony fish and insects
n/a
3.1.1 Exchange surfaces (2 LOs: mechanisms and
dissection)
New Plant defences against
pathogens n/a
4.1.1 Communicable diseases, disease prevention and the
immune system (1 LO)
New Autoimmune diseases n/a
4.1.1 Communicable diseases, disease prevention and the
immune system (1 LO)
New The principles and
uses of paper and thin layer chromatography
n/a
2.1.2 Biological molecules (1 two-part
LO: principles and practical investigations)
New How genetic
biodiversity may be assessed
n/a 4.2.1 Biodiversity (1
LO: includes calculations)
New Reflex actions n/a 5.1.5 Plant and animal
responses (1 LO)
Removed Diet and food
production 2.2.1 Diet and Food Production (10 LOs)
n/a
Removed Smoking 2.2.2 Health and Disease (3 LOs)
n/a
Removed Animal Behaviour 5.4.3 Animal Behaviour
(6 LOs) n/a
Moved Meiosis
5.1.2 Meiosis and variation (2 LOs: the
stages of meiosis and the significance)
Note: this is an A2 module
2.1.6 Cell division, cell diversity and cellular organisation (2 LOs: the significance of meiosis and the
stages) Note: this is an AS
module
Moved Protein synthesis
5.1.1 Cellular Control (2 LOs: how a gene
determines amino acid sequence and the
mechanism of translation)
Note: this is an A2 module
2.1.3 Nucleotides and nucleic acids (2 LOs:
how a gene determines amino acid sequence and the mechanism of
translation) Note: this is an AS
module
Moved ATP
4.4.1 Respiration (1 LO: structure of ATP) Note: this is an A2
module
2.1.3 Nucleotides and nucleic acids (1 LO: structure of ADP and
ATP) Note: this is an AS
module
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Biology B Specification Content: What is familiar from previous Biology H021/H421?
Topic Appearance in new specification
H021/H421 spec. ref. New spec. ref.
Cells
Content from both ‘cell structure’ and ‘cell
membranes’ adapted into the new ‘cells and
microscopy’ topic
1.1.1 Cell Structure and
1.1.2 Cell Membranes
2.1.1 Cells and microscopy
Water Some learning
outcomes taken from ‘biological molecules’
2.1.1 Biological Molecules
2.1.2 Water and its importance in plants
and animals
Proteins and enzymes Merging of content
from two topics
2.1.1 Biological Molecules
and 2.1.3 Enzymes
2.1.3 Proteins and enzymes
Nucleic acids Very similar content
adopted but ATP structure included
2.1.2 Nucleic Acids 2.1.4 Nucleic acids
Transport and gas exchange systems
Much content relates strongly to F212
Module 2
F212 Module 2: Exchange and
Transport
2.2 Transport and gas exchange systems
Mitosis
Much content familiar from 1.1.3 but
apoptosis added here (A2 content previously)
1.1.3 Cell Division, Cell Diversity and Cellular
Organisation
3.1.1 The developing cell: cell division and
cell differentiation
Disease Content significantly
extended from previous topic 2.2.2
2.2.2 Health and Disease
3.2 Pathogens, immunity and disease control and 3.3 Non-
communicable diseases
Respiration Concepts familiar but fitness context new
4.4.1 Respiration 4.1 Energy, metabolism
and exercise
Photosynthesis Key concepts included
as introduction to broader themes
4.3.1 Photosynthesis
4.3.1 Photosynthesis, food production and management of the
environment
Population impact
Demographics and impacts included but
without the considerations of competition and
predation
5.3.2 Populations and Sustainability
4.3.2 The impact of population increase
Genetic control
Molecular genetics and population genetics included much as
before
5.1.1 Cellular Control and
5.1.2 Meiosis and Variation
5.1.1 Patterns of inheritance and 5.1.2 Population genetics
and epigenetics
Gene Technologies Much content familiar
from 5.2.3 5.2.3 Genomes and Gene Technologies
5.1.3 Gene technologies
Nervous system
Much content familiar from 4.1.2 and 5.4.2
but with new focus on damage
4.1.2 Nerves and
5.4.2 Animal Responses
5.2.1 The nervous system and the
identification and consequences of
damage
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Biology B Specification Content: What is familiar from Human Biology H023/H423?
Topic Appearance in new specification
H023/H423 spec. ref. New spec. ref.
Cells The context of blood
cells is used 1.1.1 The Blood
2.1.1 Cells and microscopy
Water Some learning
outcomes familiar from ‘molecules’
1.1.2 Molecules 2.1.2 Water and its
importance in plants and animals
Heart function Familiar content
adapted and merged
1.2.1 The Heart and Monitoring Heart Function
and 2.4.1 CHD
2.2.1 The heart and monitoring heart function
Transport and gas exchange systems
Much content relates strongly to 1.2.2 and
1.2.3
1.2.2 The Circulatory System and 1.2.3 The
Lungs and Investigating Lung Function
2.2.2 Transport systems in mammals and 2.2.3
gas exchange in mammals and plants
Mitosis Much content familiar
from 2.1.1 2.1.1 Mitosis as Part of the
Cell Cycle
3.1.1 The developing cell: cell division and cell
differentiation
Cancer Content adapted from
2.1.2 2.1.2 Detecting and Treating
Cancer 3.3.1 The cellular basis of
cancer and treatment
Infectious Disease Significant familiar content from F222
Module 3
F222 Module 3 Infectious Disease
3.2 Pathogens, immunity and disease control
Lung Disease Similar to 2.4.2 with
more treatment focus 2.4.2 Lung Disease
3.3.2 Respiratory diseases and treatment
Respiration and exercise
Content and context both familiar from F224 Module 1
F224 Module 1 Energy and Respiration
4.1 Energy, metabolism and exercise
Mammalian reproduction
Much familiar content
4.2.1 Fertility and Contraception, 4.2.2
Assisted Reproduction, 5.4.1 The Effects of Ageing on the Reproductive System
4.2 Mammalian reproduction
Population increase
Familiar content adapted and updated
4.2.4 Food, Farming and Populations – Human
Impact on the Environment
4.3.2 The impact of population increase
Inheritance Fundamentals of
genetics remain the same
5.1.1 Inheritance of Human Genetic Disease
5.1.1 Patterns of inheritance
Gene Technologies Much content familiar
from 5.1.2 5.1.2 Genetic Techniques 5.1.3 Gene technologies
Nervous system
Much content familiar from 5.2.1, 5.2.2 and 5.2.3 but with extra material from 5.4.2
5.2.1 Monitoring Visual Function and 5.2.2 Treating
Central Nervous System Injuries and 5.2.3 Modifying
Brain Function and 5.4.2 The Effects of Ageing on
other Body Systems
5.2 Nervous control
Homeostasis Familiar key concepts 5.3.1 The Importance of
Homeostasis
5.3.1 The principles and importance of homeostasis
Blood glucose Familiar example of
hormonal control 5.3.2 Managing Type 1 and
Type 2 Diabetes
5.3.2 The hormonal control of blood glucose and the management of
diabetes
Kidney Function and
treatment topics merged
5.3.3 Urine Production and 5.3.4 Treating Kidney
Disease
5.3.3 Kidney functions and malfunctions
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Multiple Choice Questions (MCQs)
Multiple Choice Questions
These have been introduced to increase the breadth of coverage of the assessment at both AS and A Level. Contrary to a widespread belief among students these questions are not easy – they are set at low, medium and high demand. It is perfectly possible to include practical skills questions and questions requiring level 2 maths within the multiple choice section.
Answer = B
Answer = C
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Maths Questions
Definition of Level 2 mathematics
Within A Level Biology, 10% of the marks available within written examinations will be for assessment of mathematics (in the context of biology) at a Level 2 standard, or higher. Lower level mathematical skills will still be assessed within examination papers but will not count within the 10% weighting for biology. The following will be counted as Level 2 (or higher) mathematics:
application and understanding requiring choice of data or equation to be used
problem solving involving use of mathematics from different areas of maths and decisions about direction to proceed
questions involving use of A level mathematical content (as of 2012), e.g. use of logarithmic equations.
The following will not be counted as Level 2 mathematics:
simple substitution with little choice of equation or data
structured question formats using GCSE mathematics (based on 2012 GCSE mathematics content). Additional guidance on the assessment of mathematics within biology is available on Interchange as a separate resource, the Maths Skills Handbook.
proportion of polymorphic gene loci = no. of polymorphic gene loci
total no. of loci
Answer = B
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Practical Questions
Examples
15% of the new assessments at AS and A Level will be on practical skills, covering planning, implementing,
analysis and evaluation in appropriate biological contexts.
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Graphs: unifying practice across Biology, Chemistry and Physics
For clarity and consistency, especially for students studying two or more sciences, we have agreed
common guidelines for practical skills and maths skills. The relevant handbooks have been prepared with
this in mind.
Note: In the previous OCR AS/A2 Biology specification (H021/H421) the guidance for line graphs stated
that ‘straight lines should join points’. For the OCR AS and A Level Biology qualifications for first teaching
from September 2015 (H020/H420, H022/H422) the guidance has changed. If a trend can be identified a
line (or curve) of best fit should be drawn as described above. If no trend can be identified, or if the nature
of the data means interpolation between data points is not appropriate, straight lines can be used to join
points if this increases the clarity of presentation. This unifies practice across the three sciences:
Chemistry, Physics and Biology.
Note: Extrapolation of a line of best fit can be done where appropriate. For example it might be necessary to extrapolate back to discover the intercept with the y axis. Where the purpose of the graph is to present the data within the experimental range only (with the possibility for deriving predicted values through interpolation) no extrapolation is needed and the line should be confined to the range of the independent variable. This unifies practice across the three sciences: Chemistry, Physics and Biology.
Adopting the ‘Language of Measurement’ from the ASE
The 2010 publication ‘The Language of Measurement’ from the Association for Science Education and the Nuffield Foundation offered a common understanding of important terms in practical work. These have already been adopted in OCR GCSE science and have now been adopted for the reformed GCE Biology, Chemistry and Physics qualifications for first teaching from September 2015. A list of the most useful terms is available in the Practical Skills Handbook, for example:
Accuracy is a measure of the closeness of agreement between an individual test result and the true value. If a test result is accurate, it is in close agreement with the true value. An accepted reference value may be used as the true value, though in practice the true value is usually not known. Precision is the closeness of agreement between independent measurements obtained under the same conditions. It depends only on the distribution of random errors (i.e. the spread of measurements) and does not relate to the true value. Resolution is the smallest change in the quantity being measured that can be detected by an instrument. Validity can apply to an individual measurement or a whole investigation. A measurement is valid if it measures what it is supposed to be measuring. An investigative procedure is valid if it is suitable to answer the question being asked. Validity will be reduced, for example, if no negative control is included in an investigation into the efficacy of a therapeutic drug. The ASE booklet The Language of Measurement (Campbell 2010) provides information on these and other terms along with examples of their use. In particular please note that Reliability will no longer be used. As the authors of the booklet say:
“The word ‘reliability’ has posed particular difficulties because it has an everyday usage and had
been used in school science to describe raw data, data patterns and conclusions, as well as
information sources. On the strong advice of the UK metrology institutes, we avoid using the word
‘reliability’ because of its ambiguity. For data the terms ‘repeatable’ and ‘reproducible’ are clear and
therefore better. For conclusions from an experiment, evaluative statements can mention
‘confidence’ in the quality of the evidence.
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Level of response questions
Marking ‘Level of Response’ Questions
Read through the whole answer from start to finish, concentrating on features that make it a stronger or weaker answer using the indicative scientific content as guidance. The indicative scientific content indicates the expected parameters for candidates’ answers, but be prepared to recognise and credit unexpected approaches where they show relevance. Using a ‘best-fit’ approach based on the science content of the answer, first decide which set of level descriptors, Level 1, Level 2 or Level 3, best describes the overall quality of the answer using the guidelines described in the level descriptors in the mark scheme. Once the level is located, award the higher or lower mark. The higher mark should be awarded where the level descriptor has been evidenced and all aspects of the communication statement (in italics) have been met. The lower mark should be awarded where the level descriptor has been evidenced but aspects of the communication statement (in italics) are missing. In summary:
The science content determines the level.
The communication statement determines the mark within a level.
Exemplar Candidate Work
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AS and A Level Biology
Copyright © OCR 2016
SECOND QUESTION:
AS Level Biology A
H020/02 Depth in biology
Sample Question Paper
Question 4(b)
4 Haemoglobin is a protein that carries oxygen in the blood of all mammals. The structure of haemoglobin can vary slightly between species.
Fig. 4.1 shows a llama, a relative of the camel.
• Llamas live at high altitudes and camels live at low altitudes.
• At high altitudes the partial pressure of oxygen is low.
• Llama and camel haemoglobin consists of 2 α subunits and 2 β subunits.
• Each subunit contains a haem group and is able to bind to one molecule of oxygen.
• In the β subunits, one amino acid present in camel haemoglobin has been replaced by a different amino acid in llama haemoglobin.
Question 2 (with mark scheme)
Fig. 4.1
Exemplar Candidate Work
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AS and A Level Biology
Copyright © OCR 2016
Fig. 4.2 shows dissociation curves for llama haemoglobin and camel haemoglobin.
(b)* Describe how the structure of llama haemoglobin is likely to be different from that of camel haemoglobin with reference to the four levels of protein structure.
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Fig. 4.2
This question requires candidates to consider how likely the structure of llama haemoglobin would differ from that of the camel. As would be the case in live marking, looking at a range of candidate responses has resulted in the mark scheme for this question being applied with the following amendments to the Level descriptors in the left hand column of the mark scheme:
Level 3 Describes differences (and similarities) of llama and camel …
Level 2 Describes differences (and similarities) of llama and camel …
Similarities are not required to meet the Level descriptors but their inclusion would not be considered irrelevant for the purposes of communication, as reference to similarity would indicate the degree to which they might differ.
As candidates have been given information in the stem of the question (all the information on page 10 of the specimen question paper, which is shown here on page 14-15), they would be expected to select and use information to justify the differences that they propose (i.e. the different amino acid present in the β chain of the llama haemoglobin). When considering the communication at Levels 1 and 2, this evidence must be stated (Level 1) and linked clearly to the differences suggested (Level 2).
16 © OCR 2015
Exemplar Candidate WorkAS and A Level Biology
Question Answer Marks Guidance(b)* Level 3 (5–6 marks)
Describes differences and similarities of llama and camel haemoglobin at all four levels of protein structure with correct reference to bonding.
There is a well-developed line of reasoning which is clear and logically structured. The information presented is relevant and substantiated.
Level 2 (3–4 marks) Describes differences and similarities of llama and camel haemoglobin in some levels of protein structure with some reference to bonding.
There is a line of reasoning presented with some structure. The information presented is in the most-part relevant and supported by some evidence.
Level 1 (1–2 marks) Describes a difference or similarity of llama and camel haemoglobin at a level of protein structure.
The information is basic and communicated in an unstructured way. The information is supported by limited evidence and the relationship to the evidence may not be clear.
0 marks No response or no response worthy of credit.
6 Indicative scientific points include:
• difference in primary structure• different amino acid / polypeptide sequence• one amino acid changed.
• amino acid change could cause change to secondary structure
• initial coiling or folding of polypeptide chain• α-helix• β-pleated sheet• hydrogen bonding.
• amino acid change could cause change to tertiary structure
• further coiling of secondary structure• ionic bonding• disulphide bonds• hydrophilic/hydrophobic bonds• 3D shape.
• amino acid change has not changed quaternary structure
• alpha and beta subunits still able to form haemoglobin in both camel and llama.
LoR Mark Scheme Qu4(b) AS Level Biology A, H020/02
Exemplar Candidate Work
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AS and A Level Biology
Copyright © OCR 2016
Level 3, 6 marks (Candidate 6)
Examiner commentaryCandidate 6 6 marks
This candidate’s response addresses all of the science content required for the Level 3 descriptor in the left hand column of the mark scheme and the science is correct.
The line of reasoning meets the guidelines in the communication statement in the left hand column of the mark scheme – it flows and reads well, with clarity.
Question 2, Sample answers and commentaryThis section includes seven candidate responses, which have been selected to show answers worthy of 6, 5, 4, 3, 2, 1 and 0 marks.
Exemplar Candidate Work
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AS and A Level Biology A
Copyright © OCR 2016
Level 2, 3 marks (Candidate 2)
Examiner commentaryCandidate 2 3 marks
Although all four levels of protein structure are considered, and there is some correct reference to bonding, there is also an incorrect statement relating to peptide bonds.
While the first part of the answer is reasonably structured, it is not clear which level of protein structure the remainder of the answer refers to. The lack of structure and reasoning, particularly in the latter part of the answer, detracts from the flow of the answer; therefore, the lower mark within the Level is awarded.