Learning Guide: Meiosis

Bill Activity #33

To Think About: How is heritable information passed to the next generation in eukaryotes, and how do changes in genotype result in changes in phenotype of an organism?

1st Read About: Meiosis and Sexual Life Cycles Pgs. 248-260 Campbell’s Biology 9th edition

Overview: Explain the importance of the principles of heredity and variation. Define genetics.

Offspring acquire genes from parents by inheriting chromosomes.

  • Define the following terms as you read: genes, gametes, somatic cells, locus
  • Describe the difference between sexual and asexual reproduction.

Fertilization and meiosis alternate in sexual life cycles.

  • Define the following terms as you read: karyotype, homologous chromosomes, sex chromosomes, autosomes, diploid cell, haploid cell, zygote, fertilization, meiosis, alternation of generations

Meiosis reduces the number of chromosome sets from diploid to haploid

  • Explain the relationship among these words: gene, DNA, chromosome, chromatid.
  • Explain why meiosis is often called “reduction division.”
  • Create a graphic organizer that illustrates the differences between meiosis and mitosis. (see pg. 256-7)

Genetic variation produced in sexual life cycles contributes to evolution

  • Explain how each of the following contribute to genetic variety among members of the same species:

1.Independent assortment of chromosomes

2.Crossing over

3.Random fertilization

2nd Interact: Take notes on Mr. Andersen’s 028 Cell Cycle, Mitosis and Meiosis Video (if you haven’t already)

3rd Interact: Take notes Mr. Andersen’s Mr. Andersen’s “Meiosis”video

Then: Mr. Andersen’s “Diploid vs. Haploid Cells” video

4th Read About: Alterations of chromosome number or structurePgs. 297-300 Campbell’s Biology 9th edition

Abnormal chromosome number

  • Explain the following terms: aneuploidy, monosomic, trisomic, polyploidy,

Alteration of chromosome structure

  • List several ways that chromosomes could be altered
  • Describe three genetic disorders that can result from nondisjunction or alterations during meiosis.

Supplementary Resources: Click the links below for more information to help you learn more about this lesson.

  • Crash Course Biology: Heredity
  • Crash Course Biology: Meiosis
  • SumanasInc: Meiosis Animation
  • Biocoach: Meiosis
  • Hillis et al.:Independent Assortment of Alleles Animation

Learn More: For more information about inheritance of traits and production of gametes, follow the links below:

  • Nondisjunction in Humans: learn how gametes can end up with extra chromosomes
  • PBS’ The Evolution of Sex: learn why sexual reproduction is advantageous from an evolutionary standpoint