Unpacked Content
Scientific and Engineering Practices
Developing and Using Models; Analyzing and Interpreting Data; Using Mathematics and Computational Thinking
Crosscutting Concepts
Patterns; Systems and System Models
Knowledge
Students know:
- Inheritable genetic variations may result from: new genetic combinations through meiosis, viable errors occurring during replication, and mutations caused by environmental factors.
- Variations in genetic material naturally result during meiosis when corresponding sections of chromosome pairs exchange places.
- Genetic material is inheritable.
- Genetic variations produced by mutations and meiosis are inheritable.
- The difference between genotypic and phenotypic ratios and percentages.
- Examples of genetic crosses that do not fit traditional inheritance patterns (e.g., incomplete dominance, co-dominance, multi-allelic, polygenic) and explanations as to how the observed phenotypes are produced.
- Mendel's laws of segregation and independent assortment.
- Pedigrees can be used to infer genotypes from the observation of genotypes.
- By analyzing a person's family history or a population study, disorders in future offspring can be predicted.
Skills
Students are able to:
- Perform and use appropriate statistical analysis of data, including probability measures to determine the relationship between a trait's occurrence within a population and environmental factors.
- Differentiate between homozygous and heterozygous allele pairings.
- Create Punnett squares to predict offspring genotypic and phenotypic ratios.
- Explain the relationship between the inherited genotype and the visible trait phenotype.
- Examine genetic crosses that do not fit traditional inheritance patterns (incomplete dominance and co-dominance).
- Use chromosome models to physically demonstrate the points in meiosis where Mendel's laws of segregation and independent assortment are observed.
- Analyze pedigrees to identify the patterns of inheritance for specific traits/ disorders including autosomal dominant/ recessive as well as sex-linked and mitochondrial patterns.
Understanding
Students understand that:
- In sexual reproduction, chromosomes can sometimes swap sections during the process of meiosis, 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.
- Environmental factors can also cause mutations in genes, and viable mutations are inherited.
- Environmental factors also affect expression of traits, and hence affect the probability of occurrences of traits in a population.
- The variation and distribution of traits observed depends on both genetic and environmental factors.
Vocabulary
- Genetics
- Allele
- Dominant
- Recessive
- Homozygous
- Heterozygous
- Genotype
- Phenotype
- Law of segregation
- Hybrid
- Law of independent assortment
- F1 and F2 generations
- Monohybrid
- Dihybrid
- Punnet square
- Probability
- Crossing over
- Genetic recombination
- Carrier
- Pedigree
- Incomplete dominance
- Codominance
- Multiple alleles
- Epistasis
- Sex chromosome
- Autosome
- Sex-linked trait
- Polygenic trait
