In short
Edexcel IGCSE Science (Double Award) 4SD0 is one qualification with three 2-hour papers (biology, chemistry, physics) and a double grade from 9-9 to 1-1. Its biology paper is the same paper as Biology 4BI1 Paper 1. Triple students also sit 4BI1 Paper 2, which adds 42 biology statements the Double Award leaves out.
The short answer: Edexcel International GCSE Science (Double Award), code 4SD0, covers biology, chemistry and physics in one qualification with three 2-hour papers and a double grade from 9-9 to 1-1. Separate sciences (often called triple) means three qualifications, one of them Biology 4BI1, each graded 9 to 1. For biology, the difference is simple: a Double Award student sits the same biology paper as a 4BI1 student's Paper 1, and a 4BI1 student also sits Paper 2, which tests 42 extra statements printed in bold in the specification.
Everything below comes from Pearson's published specifications for 4SD0/2017/specification-and-sample-assessments/international-gcse-science-double-award-2017-specification1.pdf) and 4BI1. We have free notes, exam questions and flashcards for both: the Edexcel IGCSE Double Award course and the Edexcel IGCSE Biology course.
Double Award vs triple at a glance
| Science (Double Award) 4SD0 | Biology 4BI1 (one of the three separate sciences) | |
|---|---|---|
| What it is | One qualification covering biology, chemistry and physics | One qualification in biology only (chemistry 4CH1 and physics 4PH1 are separate qualifications) |
| Papers | 3: Biology Paper 1, Chemistry Paper 1, Physics Paper 1 | 2: Biology Paper 1 and Biology Paper 2 |
| Biology papers | Biology Paper 1 (4SD0/1B, same as 4BI1/1B): 2 hours, 110 marks, 33.3% of the Double Award | Paper 1 (4BI1/1B): 2 hours, 110 marks, 61.1%. Paper 2 (4BI1/2B): 1 hour 15 minutes, 70 marks, 38.9% |
| Total marks | 330 (110 per science) | 180 (110 + 70) |
| Grades | 17-grade scale, 9-9 to 1-1 | 9 to 1 |
| Biology content | 4BI1 content without the bold "B" statements | All the content, including the 42 "B" statements |
| Biology practicals in the spec | 9 | 14 |
| Tiers | None | None |
| Exam series | June and November | June and November |
What is Edexcel IGCSE Science (Double Award) 4SD0?
The specification describes 4SD0 as a linear qualification of three externally assessed papers: Biology Paper 1, Chemistry Paper 1 and Physics Paper 1. Each is a 2-hour written exam worth 110 marks and 33.3% of the total, and all three must be taken in the same series at the end of the course. The papers mix multiple-choice, short-answer, calculation and extended open-response questions, and a calculator may be used. There is no coursework and no practical exam: experimental skills are tested in the written papers.
Pearson says the content is "of equivalent standard to Pearson's regulated GCSE in Combined Science". Like the rest of the International GCSE range, it is untiered, so every student sits the same papers and can reach the top grade.
Is IGCSE Double Award two IGCSEs?
Double Award is one qualification with a double grade. The specification says it is "graded and certificated on a 17-grade scale from 9-9 to 1-1 using the total subject mark, where 9-9 is the highest grade". The scale runs 9-9, 9-8, 8-8, 8-7 and so on down to 1-1, so the two numbers can differ by one. Individual papers are not graded: your marks from all three papers are added together (out of 330) and one double grade is awarded. You do not get a separate biology grade.
The specification does not use the words "two International GCSEs", so how a double grade is counted (for example, towards a requirement for a number of passes) is up to each school, sixth form or university. If it matters for your plans, ask the institution directly.
Thinking a Double Award biology grade exists on its own. It does not: a strong biology paper can be pulled down by weaker chemistry or physics, and the other way round, because the grade comes from the total mark across all three papers.
4SD0 vs 4BI1: the biology papers
This is the part most students do not realise. The Double Award biology paper has two codes, 4BI1/1B and 4SD0/1B: it is the same paper that Biology students sit as Paper 1. It lasts 2 hours, carries 110 marks and "assesses core content that is not in bold and does not have a 'B' reference".
4BI1 students then sit Biology Paper 2 (4BI1/2B): 1 hour 15 minutes and 70 marks. It "assesses all the content, including content that is in bold and has a 'B' reference", so it can ask about anything in the course, not only the bold points. The 4BI1 papers are not scaled: 110 + 70 = 180 marks, graded 9 to 1. In both courses, about 19 to 21% of the marks test experimental skills (assessment objective AO3).
So for biology, a Double Award student prepares for one paper, and a Biology student prepares for that same paper plus Paper 2. For more on how the two 4BI1 papers differ, see our Edexcel IGCSE Biology Paper 1 and Paper 2 guide, and for how marks are given, how IGCSE Biology is marked. Official papers are linked from the Edexcel IGCSE Biology past papers and Double Award past papers pages.
Double Award biology topics
Both courses use the same five biology topics, with the same numbering: the nature and variety of living organisms, structure and functions in living organisms, reproduction and inheritance, ecology and the environment and use of biological resources.
The 4BI1 specification has 176 biology statements and the 4SD0 biology section has 134. The 42 missing from the Double Award are exactly the ones marked in bold with a "B" after the number, and the 4SD0 document keeps the 4BI1 numbers, so it jumps from 2.4 to 2.7 with a note that "Specification points 2.5 and 2.6 are in the Pearson Edexcel International GCSE in Biology only." Topic 1 has no B statements at all, and most of the gap is in topic 2.
Biology content in 4BI1 but not in the Double Award
We built this table statement by statement from the two specifications. Everything here is "Biology only": it is tested on 4BI1 Paper 2 and is not in the Double Award.
| Sub-topic | Spec points | Biology-only content |
|---|---|---|
| Cell structure | 2.5B, 2.6B | Cell differentiation and specialised cells; advantages and disadvantages of stem cells in medicine |
| Biological molecules | 2.14B | Practical: how pH affects enzyme activity |
| Human nutrition | 2.33B | Practical: energy content of a food sample |
| Gas exchange in flowering plants | 2.40B to 2.45B | Diffusion in gas exchange; gas exchange in relation to respiration and photosynthesis; leaf adaptations for gas exchange; stomata; net gas exchange depending on light intensity; practical with hydrogen-carbonate indicator |
| Transport in flowering plants | 2.55B to 2.58B | Water uptake by root hair cells; transpiration; effect of humidity, wind speed, temperature and light intensity; practical on transpiration rate from a leafy shoot |
| Blood and immunity | 2.63B, 2.64B | Vaccination and memory cells; platelets and blood clotting |
| Excretion in humans | 2.72B to 2.79B | The kidney in excretion and osmoregulation; urinary system; nephron structure; ultrafiltration and glomerular filtrate; water reabsorption; selective reabsorption of glucose; ADH; composition of urine |
| Hormones | 2.95B | Sources, roles and effects of ADH, FSH and LH |
| Human reproduction | 3.10B | Roles of FSH and LH in the menstrual cycle |
| DNA and protein synthesis | 3.16B to 3.18B | DNA double helix and base pairing; RNA and uracil; transcription and translation (mRNA, tRNA, ribosomes, codons, anticodons) |
| Inheritance | 3.21B | Codominance |
| Mutation | 3.35B to 3.37B | How a DNA change can alter a protein and the phenotype; most mutations have no effect; ionising radiation and chemical mutagens |
| The organism in the environment | 4.3B, 4.4B | Biodiversity; practical measuring distribution and biodiversity with quadrats |
| Cycles within ecosystems | 4.11B | The nitrogen cycle |
| Human influences on the environment | 4.18B | Effects of deforestation |
| Food production | 5.9B | Fish farming |
| Cloning | 5.17B to 5.20B | Micropropagation (tissue culture); cloning mammals (Dolly the sheep); cloned transgenic animals that make human proteins |
On our site the Biology-only sections are labelled inside the 4BI1 notes, for example excretion, transport in plants, gas exchange in flowering plants, DNA, genes and protein synthesis, cycles within ecosystems and cloning, which is the one whole sub-topic that is Biology only. The Double Award course leaves these sections out, so Double Award students can revise without wading through content they will not be examined on.
Tick your way through the Double Award specification checklist or the Biology specification checklist, which marks the B statements. If you are a Biology student, give the B points extra time before Paper 2.
Practicals: 9 vs 14
Practicals are printed in italics in both specifications and tested in the written exams. 4BI1 lists 14 biology practicals; 5 of them are B statements, which leaves 9 in the Double Award. The five Biology-only practicals are pH and enzyme activity, energy content of food, light and net gas exchange, transpiration with a potometer and distribution and biodiversity. Shared practicals include food tests and temperature and enzyme activity. See the full lists on the Double Award practicals and Biology practicals pages.
Science Double Award vs separate sciences: who each suits
Pearson does not say one route is for stronger students. Both are untiered, both are graded up to 9 (or 9-9), and the 4SD0 specification lists the same progression routes as separate sciences, including International AS and A Level, GCE A Level and the IB. What differs is the amount of content and exam time.
- Double Award gives broad coverage of all three sciences with less content in each. For biology that is 134 statements and one 2-hour paper. It suits students who want science to take up less of their timetable, and it frees space for other subjects.
- Separate sciences go deeper. For biology alone that is 176 statements and 3 hours 15 minutes of exams, including topics such as the kidney, protein synthesis and the nitrogen cycle. They suit students who enjoy science, or who want to meet these topics before studying biology further.
- Planning A Level or IB Biology? Both routes are listed as leading to it, but the B content (kidney, protein synthesis, hormones in the menstrual cycle) comes up again at the next level. A Double Award student can read our 4BI1 notes on those topics over the summer.
In practice, your school usually decides which route is offered, or sets students into the two routes. Entry requirements for sixth forms and universities are set by each institution, so check them directly rather than relying on general advice.
Switching between Double Award and Biology
Because Biology Paper 1 is shared, switching is easier than between most courses. Two rules from the specifications matter. First, 4SD0 and 4BI1 are forbidden combinations: you cannot be entered for both (4SD0 also cannot be taken alongside 4CH1 or 4PH1). Second, each is linear, so all of its papers must be taken in the same series.
- Double Award to Biology: everything you have learned still counts towards Paper 1. Add the 42 B statements in the table above, practise the five extra practicals, and get used to Paper 2, which can ask about the whole course.
- Biology to Double Award: you already know all the biology. Drop the B content from your revision, and put the time into chemistry and physics, which share the grade.
- Joining from another board: compare our Cambridge vs Edexcel IGCSE Biology and IGCSE vs GCSE Biology guides, then work through the checklist for your new course.
Revising for either route
Double Award students: start from the Double Award revision notes, test yourself with exam questions and topic tests, and use the flashcards. Biology students: use the 4BI1 revision notes, exam questions, topic tests and flashcards, which include the B content.
If you want help with either route, or with a switch between them, we offer 1-to-1 biology tutoring online and in Dubai.
Sources: Pearson Edexcel International GCSE Science (Double Award) 4SD0 specification/2017/specification-and-sample-assessments/international-gcse-science-double-award-2017-specification1.pdf), Pearson Edexcel International GCSE Biology 4BI1 specification and the Pearson International GCSE Science (Double Award) page.