HS-LS3-2 | Sources of Genetic Variation
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, (3) mutations caused by environmental factors and/or (4) genetic engineering.
Clarification statement: Emphasis is on using data to support arguments for the way variation occurs including the relevant processes in meiosis and advances in biotechnology.
Assessment boundary: Assessment does not include recalling the specific details of the phases of meiosis or the biochemical mechanisms of the specific phases in the process.
Assessment
What assessment of HS-LS3-2 might look like on a NY state exam.
Performance Level Descriptions
PLDs communicate the knowledge and skills expected of students to demonstrate proficiency in each Learning Standard. NYS assessments classify student performance into one of five levels.
Vocabulary
Terms from the Biology Glossary that come from this standard or from the released exam questions that assess it.
- argument
- biotechnology
- cell
- chromosome
- claim
- correlation (versus cause)
- DNA replication
- empirical evidence
- environmental factor
- gene
- genetic combination
- genetic engineering
- genetic variation
- genetically modified
- inheritable variation
- meiosis
- mutation
- population
- probability
- replication error
- sex cell
- sexual reproduction
- trait
- variation
- allele – June 2026, June 2025
- allergy – Jan 2026
- blood – June 2025
- body cell – June 2026, Aug 2025
- coloration – Aug 2026
- CRISPR-Cas9 (gene editing) – Jan 2026
- cross (genetic cross) – June 2026
- differentiation – Aug 2026
- DNA – Aug 2026, June 2026, Jan 2026, Aug 2025, June 2025, Sample 2024
- DNA sequence – Jan 2026, Sample 2024
- egg (egg cell) – Aug 2026, Jan 2026
- enzyme – Sample 2024
- fraternal twins – Jan 2026
- gamete – June 2026, June 2025
- gene expression – June 2025
- gene therapy – Aug 2025
- generation – June 2026, Aug 2025, June 2025
- genetic technology – Jan 2026
- genotype – June 2026
- hybrid – June 2026
- inflammatory response – Sample 2024
- insertion (mutation) – June 2026
- keratinocyte – Aug 2025
- methylation (and demethylation) – June 2025
- mitosis – Aug 2026, June 2026, Aug 2025, June 2025
- neuron (nerve cell) – June 2026
- nucleic acid – June 2025
- oxygen – June 2025
- parental generation (P) and F1, F2 generations – June 2026
- phenotype – June 2026
- pigment – Aug 2026
- prostaglandin receptor – Sample 2024
- protein – Jan 2026, Sample 2024
- recombination – Aug 2026
- reproduction – Sample 2024
- reproductive cell – Jan 2026
- salivary gland – Jan 2026
- skin – Aug 2026, Jan 2026
- skin cell – Aug 2025
- sperm – Aug 2026, Jan 2026
- spore – Aug 2026
- sugar – Sample 2024
- ultraviolet radiation – Aug 2026
- variant (gene variant) – June 2026
- zygote – Aug 2026
- crossing over – implied by "chromosomes can sometimes swap sections during the process of meiosis"
Resources
Examples and discussion of resources for the learning, teaching, and assessment of HS-LS3-2.
NGSS Dimensions
Performance expectation HS-LS3-2 was developed using the following elements from the NRC document A Framework for K-12 Science Education:
- Engaging in Argument from Evidence
- Make and defend a claim based on evidence about the natural world that reflects scientific knowledge, and student-generated evidence.
- LS3.B: Variation of Traits
- In sexual reproduction, chromosomes can sometimes swap sections during the process of meiosis (cell division), thereby creating new genetic combinations and thus more genetic variation. Although DNA replication is tightly regulated and remarkably accurate, errors do occur and result in mutations, which are also a source of genetic variation.
- (NYSED) Environmental factors can cause mutations in genes. Only mutations in sex cells can be inherited.
- (NYSED) Advances in biotechnology have allowed organisms to be modified genetically.
- Environmental factors also affect expression of traits, and hence affect the probability of occurrences of traits in a population. Thus the variation and distribution of traits observed depends on both genetic and environmental factors.
- Cause and Effect
- Empirical evidence is required to differentiate between cause and correlation to make claims about specific causes and effects.