Box-and-whisker plots summarize variation using median, quartiles, range and outliers for comparing data distributions in inheritance problems in inheritance problems.
Coverage 2025–2025 · Updated 16 Jul 2026
A box-and-whisker plot summarizes a continuous dataset using the minimum, lower quartile (Q1), median, upper quartile (Q3), maximum and any plotted outliers.
The box spans the middle 50% of observations, its internal line is the median, and whiskers show the non-outlying range when outliers are plotted separately.
To compare two student-height samples, compare their medians for centre, their IQRs for spread, their total non-outlying ranges and any outliers.
A longer box means a larger IQR, not necessarily a larger sample. A box plot does not display every observation or prove that two groups differ significantly.
This objective is assessed through data analysis, commonly using State / Determine / Deduce.
State / Determine / Deduce
Build the answer around this relationship: The median is the central line, not the mean.
Representative question
Using the data, deduce whether the incidence of CHF or the incidence of anemia has a greater effect on the blood hepcidin concentration.
Core D3.2 is secure when the student can move from allele rules into predictions and evidence: gametes form genotypes, genotypes can produce phenotypes, different dominance patterns need different notation, and pedigrees or plots require evidence-based interpretation.
Core inheritance exam questions reward disciplined reasoning. First identify the inheritance rule, then write the correct notation or evidence, then state the phenotype, ratio, or conclusion. This prevents the common mistake of writing definitions without solving the genetic problem.
