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Biology

Through studying biology, students should become aware of how scientists work and communicate with each other.  In all group 4 subjects there is an emphasis on a practical approach through experimental work.  The group 4 project (which all science students must undertake), mirrors the work of real scientists by encouraging collaboration between schools across the regions.

Past experience shows that students will be able to study a group 4 subject at standard level (SL) successfully with no background in, or previous knowledge of science.  For most students considering the study of a group 4 subject at higher level (HL) however, some previous exposure to the specific subject would be necessary.  Students who have undertaken the IB Middle Years Programme (MYP) would be well prepared.  Other national science qualifications or a school-based science course would also be suitable preparation for study of a group 4 subject at HL.  A biology students’ approach to study should be characterized by the specific IB learner profile attributes – inquirers, thinkers and communicators.

The biology course is organized by topics, SL students study six topics and HL students study a further five, with some of these taking the first six topics to greater depth.  In addition to this, both SL and HL students study two out of a choice of seven (at SL) or five (at HL) option topics.  There are four basic biological concepts that run throughout:

  • Structure and function; this relationship is probably one of the most important in a study of biology and operates at all levels of complexity.  Students should appreciate that structures permit some functions while, at the same time, limiting others.
  • Universality versus diversity; at the factual level, it soon becomes obvious to students that some molecules (for example, enzymes, amino acids, nucleic acids and ATP) are ubiquitous and so are processes and structures. However, these universal features exist in a biological world of enormous diversity.  Species exist in a range of habitats and show adaptations that relate structure to function.  At another level, students can grasp the idea of a living world in which universality means that a diverse range of organisms (including ourselves) are connected and interdependent.
  • Equilibrium within systems; checks and balances exist both within living organisms and within ecosystems.  The state of dynamic equilibrium is essential for the continuity of life.
  • Evolution; the concept of evolution draws together the other themes.  It can be regarded as change leading to diversity within constraints and this leads to adaptations of structure and function.

These four concepts serve as themes that unify the various topics that make up the three sections of the course: the core, the additional higher level (AHL) material and the options.

The order in which the syllabus is arranged is not the order in which it should be taught and it is up to individual teachers to decide on an arrangement that suits their circumstances.  Option material may be taught within the core or the AHL material, if desired.

The power of scientific knowledge to transform societies is unparalleled. It has the potential to produce great universal benefits or to reinforce inequalities and cause harm to people and the environment. In line with the IB mission statement, group 4 students need to be aware of the moral responsibility of scientists to ensure that scientific knowledge and data are available to all countries on an equitable basis and that they have the scientific capacity to use this for developing sustainable societies.

The current biology course is under review and teaching of this new course will begin in September 2014, with first examinations in May 2016.

Key features of the curriculum and assessment models

  • Available at both SL and HL
  • The minimum prescribed number of hours is 150 for SL and 240 for HL
  • Biology students at SL and HL undertake a common core syllabus, a common internal assessment (IA) scheme and have some overlapping elements in the options studied.
  • While the skills and activities related to biology are common to both SL and HL students, students at HL are required to study some topics in greater depth, to study additional topics and to study extension material of a more demanding nature in the common options. The distinction between SL and HL is one of breadth and depth.
  • An experimental approach to the course delivery is emphasised.
  • Students are assessed both externally and internally
  • The external assessment of biology consists of three written papers.  In paper 1 there are 30 (at SL) or 40 (at HL) multiple-choice questions.  Paper 2 has two sections; section A contains one data-based question and several short-answer questions on the core (and AHL material at HL) which are all compulsory.  Paper 2, section B consists of one extended-response question on the core from a choice of three at SL and two extended-response questions on the core and the AHL from a choice of four at HL.  Paper 3 consists of several compulsory short-answer questions in each of the two options studied.  In addition, at HL there is one extended-response question in each of the two options studied.
  • Internal assessment accounts for 24% of the final assessment and consists of the interdisciplinary group 4 project and a mixture of both short-term and long-term investigations. The internal assessment allows students to demonstrate not only their scientific knowledge but also personal skills and manipulative skills.  Student work is internally assessed by the teacher and externally moderated by the IB.

Much of this information is taken directly from the biology subject guide, available to all IB teachers on the Online Curriculum Centre (OCC).

Find out more

Read about similar studies in the Middle Years Programme and Primary Years Programme.