Unit Plan 19 (Grade 7 Science): Inheritance Basics
Grade 7 unit modeling how traits are inherited: students simulate asexual copying of genes and sexual mixing of chromosomes to explain identical offspring vs variation.
Focus: Model how traits are passed through genes on chromosomes, and explain why asexual reproduction results in identical genetic information while sexual reproduction leads to variation.
Grade Level: 7
Subject Area: Science (Life Science — Inheritance & Variation; Modeling)
Total Unit Duration: 5 sessions (one week), 50–60 minutes per session
I. Introduction
In this unit, students build a core understanding of inheritance by connecting observable traits to genes and chromosomes. They begin with visible traits and family-like patterns, then use chromosome models to simulate how genetic information is passed in asexual and sexual reproduction. Through hands-on modeling and comparison, students explain why one-parent (asexual) reproduction produces offspring with identical genetic information, while two-parent (sexual) reproduction produces offspring with varied gene combinations, aligned with MS-LS3-2.
Essential Questions
- How are traits passed from parents to offspring through genes and chromosomes?
- What is the difference between asexual and sexual reproduction in terms of genetic information passed to offspring?
- Why do offspring from asexual reproduction tend to be genetically identical to the parent, while offspring from sexual reproduction show variation?
- How can models of genes and chromosomes help us explain and predict inheritance patterns?
II. Objectives and Standards
Learning Objectives — Students will be able to:
- Describe traits as observable characteristics influenced by genes carried on chromosomes.
- Explain that genes are segments of DNA located on chromosomes, and that chromosomes come in pairs in body cells.
- Develop and use chromosome models to show how asexual reproduction involves copying and passing on the same genetic information to offspring.
- Develop and use chromosome models to show how sexual reproduction combines chromosome sets from two parents, producing different gene combinations in offspring.
- Create an Inheritance Basics Comparison Model & Explanation that clearly compares asexual vs. sexual reproduction and explains why one leads to identical genetic information while the other leads to variation, aligned to MS-LS3-2.
Standards Alignment — 7th Grade (NGSS-based custom)
- MS-LS3-2 — Develop and use a model to describe why asexual reproduction results in offspring with identical genetic information while sexual reproduction results in offspring with genetic variation.
- Students use concrete chromosome models to represent copying vs. mixing of genes and explain resulting similarities and differences in offspring.
Success Criteria — Student Language
- I can define trait, gene, and chromosome and show how they are related.
- I can use a model to show how asexual reproduction copies the same chromosomes (and genes) into offspring.
- I can use a model to show how sexual reproduction mixes chromosomes from two parents, creating new gene combinations in offspring.
- I can clearly explain why asexual offspring are genetically very similar to their parent and why sexual offspring show more variation.
- I can create a final diagram or poster that compares asexual and sexual reproduction using accurate vocabulary and labeled chromosome models.