IB Biology HL 4.1.3 Transects, quadrats and population estimates Question Bank
Practise IB Biology HL 4.1.3 by evaluating transect and quadrat evidence to estimate abundance and distribution.
- Syllabus
- First assessment 2025
- Course
- Biology HL
- Level
- HL
Practise IB Biology HL 4.1.3 by evaluating transect and quadrat evidence to estimate abundance and distribution.
White sage (Salvia apiana) is a native Californian shrub. Slender oat (Avena barbata) is a grass, originally from the Mediterranean, which was introduced to California. The map shows the distribution of the two species in relation to one another in an area near Santa Ynez, California.

Using the scale bar, determine the area of quadrat A1, giving the units.
9.0 m2/9 m2
Units required for the mark.