IB Biology (HL and SL)

Specification link

Course description

Both Higher and Standard Level Biology courses start at the microscopic level by looking at cells, their structure, the biochemical molecules that determine life and in particular the structure and function of DNA. Considerable emphasis is on genetics. Human health and physiology incorporate familiar aspects such as digestion, circulation, the nervous system, reproduction and the immune system. Organisms in their environment and humanity’s effects on species are studied in the ecology topic. Plant science, evolution and metabolic processes are also studied.

The Higher level course extends the Standard Level course in a number of key areas: detailed protein structure and protein synthesis; DNA replication and advanced structure; the function of meiosis in achieving genetic diversity; dihybrid and polygenic inheritance; the processes of spermatogenesis; detailed metabolic processes in both photosynthesis and respiration; plant anatomy, reproduction and transport; kidney function and processes; muscles and movement. This is a traditional course with considerable depth. It provides a very good platform for anyone aiming to read Biological Sciences at university.

Course Structure

An overview of the course structure is shown below. Standard level students complete 6 core topics and one option topic, while higher level students complete core and 5 higher level (AHL) topics, as well as one option. All students complete compulsory practical activities and complete an Individual Investigation, a mini research project which students design and complete themselves.

Assessment Structure

The course is assessed through three final exams and the individual assessment as shown below-

 Standard LevelHigher Level
Paper 1
(multiple choice assessment of core topics)
Duration- ¾ hour
Marks- 30
Weighting- 20%
Duration- 1 hour
Marks- 40
Weighting- 20%
Paper 2
(written assessment of core topics)
Duration- 1 ¼  hour
Marks- 50
Weighting- 40%
Duration- 2 ¼hour
Marks- 72
Weighting- 36%
Paper 3
(written assessment of option topic)
Duration- 1 hour
Marks- 35
Weighting- 20%
Duration- 1 ¼hour
Marks- 25
Weighting- 34%
Individual investigationWeighting- 20% Weighting- 20%


Higher Level – Pupils will ideally have a level 7 in GCSE Biology and Chemistry

Standard Level – Everyone is welcome

While not a strict requirement, it is worth saying that, due to significant overlap of content and ideas, the Higher Level is easier when studied in combination with Chemistry.

Potential careers

Biology is essential preparation for those considering careers as doctors, dentists, vets, biochemists, botanists, ecologists, zoologists. Biology degrees can also lead into a huge range of other careers. The following link provides some information-

Royal Society of Biology careers page

Contact for more information

Mrs A G Edmunds (AGE@wellingtoncollege.org.uk)