Biology 11–12 · Year 12

Gel electrophoresis of food dyes and a size calculator for DNA fragments

Module 5: Heredity (Inheritance Patterns in a Population)

Teacher-led practicalPractical, model not builtMedium risk

Teacher-led practical

A teacher carries out this practical while the class watches. Its materials, steps, variables, misconceptions and sources are not published on the open web, and neither is any result, control or note that states a number or an amount: tutors and administrators read them on the learning platform, with the safety card first. The idea, the hazards and the curriculum references are below.

Open the procedure on the learning platform (tutor or administrator sign-in)

School laboratory, not for home

In a school laboratory, with a teacher supervising, under the school's risk assessment. Not for home.

This Lab page has no on-screen model. Where a step or a material names a model, simulation or tool, it was planned when the practical was written and is not on this site; an external simulation a step names (for example PhET) is not part of this site.

The idea

Charged molecules travel through a gel at speeds set by size and charge, and a ladder of known sizes calibrates the gel. Food dyes stand in for DNA fragments: the gel shows the separation step that DNA profiling depends on, without running any DNA and without reading an inheritance pattern.

Safety card

Medium riskTeacher-led practical

Setting: In a school laboratory, with a teacher supervising, under the school's risk assessment. Not for home.

Hazards

  • Electricity and liquid together: shock
  • Hot molten agar: scalds
  • Dyes stain

Controls

At least one of them states a number or an amount, which may be part of the method, so the controls are shown with the method to tutors and administrators on the learning platform.

Note

Low-voltage electrophoresis and molten agarose: RiskAssess (https://www.riskassess.com.au/).

What you should see

It states a number or an amount, which may be part of the method, so it is shown with the method to tutors and administrators on the learning platform.

Curriculum references

The NSW syllabus outcomes and Australian Curriculum v9 codes this practical supports. They are references, not a verified or complete curriculum alignment.

  • Biology Stage 6 Syllabus (2017), current: Year 11 taught to the end of 2026 and Year 12 to Term 3 2027BIO12-12BIO11/12-4
  • Biology 11–12 Syllabus (2025), Year 12 Working scientifically; new syllabus not yet taught: Year 11 from Term 1 2027, Year 12 from Term 4 2027BI-12WS-03BI-12WS-04
  • Australian Curriculum v9No Australian Curriculum v9 code is listed.

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