CurriculumGrade 7Science

When Genes Change: Mutations and Proteins

Aligned to MS-LS3-1 — Next Generation Science Standards.

What this lesson teaches

Genes carry instructions for building proteins, which shape an organism's traits. A structural change to a gene, called a mutation, can change the protein it makes — and that change may be harmful, beneficial, or have no effect at all.

Worked example

A mutation in the gene for skin pigment can stop a protein from forming color, producing an animal with no pigment; the same kind of change in a different gene might do nothing, showing mutations can be harmful, neutral, or occasionally helpful.

Practice questions

  1. Copy a short sentence by hand and see how changing one letter changes the meaning, like a mutation.
  2. Model a gene as a bead string, swap one bead, and describe how the built protein might change.
  3. Explain, using your model, why some mutations are harmful, some are neutral, and some are beneficial.

Watch the lesson

Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.

▶ Watch this lesson

En español

Cuando los genes cambian: mutaciones y proteínas

Los genes llevan instrucciones para construir proteínas, que dan forma a los rasgos de un organismo. Un cambio en la estructura de un gen, llamado mutación, puede cambiar la proteína que produce — y ese cambio puede ser perjudicial, beneficioso o no tener ningún efecto.

Ejemplo: Una mutación en el gen del pigmento de la piel puede impedir que una proteína forme color, produciendo un animal sin pigmento; el mismo tipo de cambio en otro gen podría no hacer nada, mostrando que las mutaciones pueden ser perjudiciales, neutrales u ocasionalmente útiles.

More Heredity: Inheritance & Variation of Traits lessons

Two Ways to Make OffspringMS-LS3-2

Teach this lesson today

An AI tutor that guides with questions instead of just giving answers — all K–12 core subjects, every child in the family.

Start free — no card required