HS-LS3-2

ScienceGrades 9–12Heredity: Inheritance and Variation of Traits

The standard

Make and defend a claim based on evidence that inheritable genetic variations may result from: (1) new genetic combinations through meiosis, (2) viable errors occurring during replication, and/or (3) mutations caused by environmental factors.

Next Generation Science Standards

What this standard means

Students need to explain where inherited variation comes from and support that explanation with evidence. They should connect variation to new allele combinations from meiosis, copying errors in DNA, and mutations caused by factors like UV light or chemicals. The focus is argument from data, not memorizing meiosis phases.

Mastery looks like a clear claim, specific evidence from a data set or scenario, and reasoning that links the evidence to an inheritance source. Students often confuse inherited mutations with body cell mutations. They may also say all mutations are harmful, or describe meiosis steps without using evidence.

Ways to teach it

  • Use colored chromosome cards to model meiosis, then have students list three different possible allele combinations from the same parents.
  • Give students a short UV exposure mutation data table and ask, “Which evidence best supports an inherited variation claim?”
  • Exit ticket: name one source of inheritable variation and write one sentence explaining what evidence would support it.
  • Connect to antibiotic resistance by having students trace how a random mutation can become common in a bacterial population.

Plan a lesson for HS-LS3-2

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Related standards

  • MS-LS1-5

    Construct a scientific explanation based on evidence for how environmental and genetic factors influence the growth of organisms.

  • HS-LS4-2

    Construct an explanation based on evidence that the process of evolution primarily results from four factors: (1) the potential for a species to increase in num...

  • 3-LS4-2

    Use evidence to construct an explanation for how the variations in characteristics among individuals of the same species may provide advantages in surviving, fi...

  • MS-LS4-4

    Construct an explanation based on evidence that describes how genetic variations of traits in a population increase some individuals' probability of surviving a...

Standard text verified against nextgenscience.org on July 10, 2026.

Page updated July 10, 2026.

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