Extended/Elective Topic Units in the 5-Unit Track
Depth in one applied area
The 5-unit track adds an elective unit chosen by the school - typical options include human genetics and genetic counselling, biotechnology and genetic engineering, neurobiology, ecology of Israeli ecosystems, or cancer biology. The examination tests depth rather than breadth: mechanisms and techniques at the molecular or system level, and the ethical and social implications argued with evidence.
Core rules
Whichever elective your class studied, the marking scheme rewards the same four moves:
- Mechanism: name the molecule, cell and signal, then link them in order.
- Technique: state the purpose, the principle and how a result is interpreted.
- Application: transfer the mechanism to a real case - a patient, a crop, a habitat.
- Evaluation: discuss risk, benefit and ethics, and support the position with specific evidence.
Elective questions still rely on core tools: probability, experimental controls, feedback loops and interpretation of data.
Worked example
In genetic counselling, a couple are both carriers of an autosomal recessive condition. Each pregnancy carries a 1/4 risk of an affected child, 1/2 of a carrier child and 1/4 of an unaffected non-carrier child. A diagnostic test such as amniocentesis or chorionic villus sampling can detect the genotype, but it carries a small procedure-related risk. Reasoning: the counsellor presents the options and their probabilities neutrally; the probability applies to each pregnancy independently, not as one in four children overall.
Marks lost
Answering the elective superficially with general statements; ignoring the ethical dimension when the item explicitly asks for it; forgetting that elective data questions are marked with the same control and significance rules as core inquiry items.