Cell Reproduction & Division: Mitosis and Meiosis

• After studying this material, you should be able to:
  • Compare and contrast how prokaryotic and eukaryotic cells reproduce asexually
  • Describe the levels of chromatin packaging that organize and protect eukaryotic genomes
  • Name the major stages of the eukaryotic cell cycle and describe what happens during each stage
  • Describe the physical changes that occur during each stage of mitosis
  • Recognize and draw eukaryotic cells in each stage of cell division
  • Compare and contrast cytokinesis in animal and plant cells
  • Explain how cyclins, cyclin-dependent kinases, and cell-cycle checkpoints regulate cell division

Key terms

• Asexual reproduction
• Clone
• Binary fission
• Cell cycle
• Chromosome
• Chromatin
• Histones
• Nucleosomes
• Metaphase chromosome
• Interphase (G1, S, G2, G0)
• Mitosis
• Prophase
• Prometaphase
• Metaphase
• Anaphase
• Telophase
• Cytokinesis
• Nucleolus
• Chromatid
• Sister chromatids
• Telomere
• Centromere
• Mitotic spindle
• Metaphase plate
• Contractile ring
• Cleavage furrow
• Cell plate
• Cyclin Cyclin-dependent kinase (cdk)
• M-promoting factor
• Cell cycle checkpoint

Topic 14

• After studying this material, you should be able to:
  • Explain the differences between haploid and diploid cells and organisms
  • Describe how prokaryotic cells divide by binary fission
  • Explain the differences between homologous and non-homologous chromosomes
  • Describe the chromosome composition of human cells
  • Compare and contrast haplontic and diplontic lifecycles
  • Describe the major differences between asexual and sexual reproduction, including their sources of genetic variation
  • Illustrate how a diploid cell with at least two pairs of homologous chromosomes generates haploid cells via meiosis
  • Explain how independent assortment and recombination contribute to genetic diversity using clearly labeled diagrams

Key terms

• Haploid
• Diploid
• Homologous chromosome
• Non-homologous chromosome
• Alleles
• Somatic cell
• Germ cell
• Egg
• Sperm
• Karyotype
• Autosome
• Sex chromosome
• Gamete
• Zygote
• Meiosis
• Meiosis I
• Meiosis II
• Prophase 1
• Metaphase 1
• Anaphase 1
• Telophase 1
• Prophase 2
• Metaphase 2
• Anaphase 2
• Telophase 2
• Tetrad Independent assortment
• Synapsis Recombination (crossing over)
• Parental chromosome
• Recombinant chromosome

Topic 15

• After studying this material, you should be able to:
  • Describe some of the early theories of heredity and how they differ from our current knowledge of how genetic traits are transmitted from one generation to the next
  • Explain the relationship between alleles, genes (DNA) and chromosomes
  • Explain how the results of Mendel's monohybrid crosses led him to propose the principle of segregation
  • Explain how the results of Mendel's dihybrid crosses led him to propose the principle of independent assortment
  • Explain how the behavior of chromosomes during meiosis leads to the segregation and independent assortment of alleles into gametes1
  • Define linkage and explain how it affects the segregation of alleles into gametes 1
  • Explain how recombination affects the segregation of linked genes during meiosis1
  • Describe how sex-linkage influences the transmission of genetic traits
  • Explain the molecular basis of incomplete dominance
  • Explain how polygenic inheritance and environment effects complicate genetic studies
  • State the gametes that can be produced by an individual given information about its genotype and the linkage of specific genes
  • Use Punnett squares and probability rules to predict the genotypes and phenotypes of progeny based on information about their parents or other family members

Key terms

• Blended inheritance
• Inheritance of acquired characteristics
• Particulate theory of heredity
• Gregor Mendel
• Mendelian genetics
• True-breeding
• Monohybrid cross
• Dihybrid cross
• Test cross
• Alleles
• Homozygous
• Heterozygous
• Dominant
• Recessive
• Genotype
• Phenotype
• Punnett Square
• Principle of Segregation
• Principle of Independent
• Assortment
• Linked genes
• Unlinked genes
• Sex (X) linkage
• Incomplete dominance
• Polygenic inheritance
• Environmental effects
• Multiplication rule
• Addition rule

Topic 16

• After studying this material, you should be able to:
  • Draw a pedigree describing the phenotypes and relationships of parents and their children across multiple generations
  • Make reasonable predications about the nature of a mutation (e.g. recessive vs dominant; X-linked vs autosomal) based on a human pedigree
  • Use Punnett squares and probability rules to predict the genotypes and phenotypes of family members and their offspring

Topic 17

• After studying this material, you should be able to:
  • Describe the molecular basis and mode of inheritance of common genetic diseases
  • Explain the contributions of heredity and the environment to cancer and other human diseases
  • Describe the possible outcomes of genetic testing and how this information is used by genetic counselors in a clinical setting

Key terms

• Pedigree analysis
• Epistasis
• Polygenic Inheritance
• Autosomal recessive disorder
• Autosomal dominant disorder
• X-linked recessive
• disorder Carrier
• Sickle cell disease
• Tay-Sachs disease
• Cystic Fibrosis
• Pathogenic mutation

Topic 17

• After studying this material, you should be able to:
  • Describe the levels at which gene expression can be regulated in prokaryotic and eukaryotic cells
  • In general terms, describe the potential advantages of various forms of gene regulation
  • With reference to the trp operon, explain the mechanism by which E. coli bacteria regulate the levels of the enzymes involved in tryptophan biosynthesis (a classic example of transcriptional regulation)
  • Explain the mechanisms used by eukaryotic cells to regulate the use of lactose, the lac operon
  • Explain the importance of sequence-specific DNA and RNA-binding proteins in the regulation of gene expression, with references to members of each class of regulatory protein and the sequences to which they bind

Key terms

• Transcriptional regulation
• Post-transcriptional regulation
• Regulation of RNA processing
• Alternative splicing
• Regulation of RNA stability
• Translational regulation
• Post-translational modification
• Regulation of protein stability
• Operon
• Polycistronic
• Trp operon
• Operator
• Trp repressor
• lac operon
• lactose