Lecture on Unit 5: Heredity

Introduction

• Focus on heredity and why it's important.
• Students referred to as 'Penguins' because they are dressed for success in taking the AP exam.

Daily Review Resources

• Daily content review on Instagram called 'insta review'.
• A 374-page review guide available on Weebly with topic questions, multiple choice, and free response questions.
• FRQ Friday videos cover all FRQs released from 2013 to present.
• 120 review games and PowerPoints available on the website.

Concepts Covered in the Lecture

Meiosis vs. Mitosis

• Discussed the stages of meiosis and how they differ from mitosis.
• Key Stages in Meiosis:
  • Prophase I: Chromatin condenses, homologous chromosomes line up, and crossing over occurs.
  • Metaphase I: Homologous chromosomes line up on the metaphase plate.
  • Anaphase I: Homologous chromosomes move apart.
  • Meiosis II: Similar to mitosis, dealing with sister chromatids.
• Differences between mitosis and meiosis highlighted in terms of chromosome behavior and genetic outcomes.

Genetic Inheritance

• Mendelian Genetics:
  • Complete dominance: Dominant allele masks recessive.
  • Co-dominance: Both alleles are visible (e.g., AB blood type).
  • Incomplete dominance: Blending of traits (e.g., blue and yellow make green).
  • Dominance does not equate to prevalence.
• Non-Mendelian Genetics: Involves linked genes and crossing over.

Chromosomal Genetics

• Explained autosomal vs. sex-linked (X-linked or chromosomal) inheritance.
• Discussed maternal inheritance through mitochondrial DNA.
• Pedigree Analysis: How to determine inheritance patterns (autosomal recessive, autosomal dominant, X-linked).

Genetic Disorders and Chromosomal Changes

• Examples include:
  • Sickle cell disease: Autosomal recessive, linked with malaria resistance.
  • Tay-Sachs: Autosomal recessive affecting brain proteins.
  • Huntington's disease: Autosomal dominant neurodegenerative disorder.
  • Down Syndrome: Result of trisomy 21.
  • Klinefelter and Turner Syndromes: Result from non-disjunction.

Phenotypic Plasticity

• Environment affects gene expression leading to different phenotypes.
• Examples include fur color in rabbits under different temperatures, diet affecting bird color, and soil pH affecting hydrangea color.

Practice Questions

• Multiple choice and free response examples to test understanding of meiosis, chromosomal genetics, and inheritance patterns.

Important Concepts for AP Exam

• Understanding of meiosis to ensure chromosome number stability.
• Analysis of genetic crosses and prediction of offspring traits through Punnett squares and ratios.
• Application of chi-square tests to genetic data to support hypotheses.

Resources for Further Study

• Instagram: AP Bio Penguins for daily reviews and FRQ Fridays.
• TikTok: AP Bio Penguins for review videos.
• AP Bio Instagram for video reviews, TikToks, and FRQ explanations.

Q&A Session

• Addressed questions about chi-square tests and genetic mapping calculations.
• Discussed the importance of understanding statistical methods and calculations for AP exam preparation.