INHERITANCE OF TRAITS
Iowa Core Alignment:
HS-LS3-1: Ask questions to clarify relationships about the role of DNA and chromosomes in coding the instructions for characteristic traits passed from parents to offspring.
HS-LS3-2: 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.
HS-LS3-3: Apply concepts of statistics and probability to explain the variation and distribution of expressed traits in a population.
Essential Question:
How is it that genetic information from parents produces offspring that look similar? Different?
Disciplinary Core Ideas:
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.
Minds on Biology (MOBs):
MOB 1: Observable Human Characteristics
MOB 2: Epigenetics *
MOB 3: Sections 10-1 and 10-4 *
MOB 4: Nature v. Nurture *
MOB 5: Mendel's Pea Plant Experiments *
MOB 6: Genetics Terms *
MOB 7: Monohybrid crosses practice
MOB 8: Dihybrid crosses practice
MOB 9: Autosomal Inheritance *
MOB 10: X-linked Inheritance *
MOB 11: Codominance and Incomplete Dominance
MOB 12: Chromosomal Inheritance
MOB 13: Polygenic Inheritance
MOB 14: Inheritance Review
MOB 15: Misconceptions about Genetics
MOB 16: ACT Prep (Epigenome) *
MOB 17: ACT Prep (Chromosome Count) *
MOB 18: Jeopardy
6.1. Traits can be expressed as a result of genetic and environmental effects.
Objectives:
(a.) Define traits and identify human traits that are inherited (nature), learned and environmentally influenced (nurture).
(b.) Define epigenome and explain how DNA methylation works and the impact it has on gene expression.
(c.) Analyze factors that can trigger the "on" and "off" switch of a gene.
(d.) Provide examples of nature (genetic influences) and nurture (environmental influences) on organisms.
Links/Sources:
Section 10-1: How cells control gene expression
Section 13-5: Nature and Nurture
Section 10-5: Epigenetics
Claim: Which daughter will most likely have breast cancer?
6.2. The inheritance of traits by offspring follows predictable rules.
Objectives:
(e.) Complete monohybrid and dihybrid Punnett squares to predict the outcome of genetic crosses and to identify dominant and recessive traits.
Links/Sources:
Section 13.1: Mendel, Pea Plants, and Inheritance Patterns
Link 1: The Fast Plant Experiment (1)
Link 2: The Pea Experiment (2)
Link 3: The Pea Experiment (G)
6.3. Inheritance patterns for single gene disorders are classified based on whether they are autosomal or X-linked, whether they have a dominant or recessive pattern of inheritance or if it is a chromosome error.
Objectives:
(f.) Summarize and differentiate between autosomal, x-linked, incomplete dominant, co-dominant, polygenetic, epigenetic and chromosomal inheritance.
(g.) Use punnett squares, pedigrees and karyotypes to detect, predict and trace genetic traits.
(h.) Use knowledge of inheritance patterns to solve genetic problems. Example: In humans, widow's peak (W) is dominant over a continuous hairline (w), and short fingers (F) are dominant over long fingers (f). Two individuals with widow's peak and short fingers have a child with continuous hairline and long fingers. Determine the genotype of the parents and probability of having an offspring with both long fingers and a widows peak.
Links/Resources:
Sections 14.2 to 14.5
Claim/Lab: How do two physically healthy parents produce one child with Down Syndrome and a second child with Cri Du Chat syndrome?