Lifestyle

• A vegan diet avoids using or consuming animal products, such as meat, eggs, and dairy.
• Meiosis ensures genetic variation through the production of non-identical gametes as a consequence of independent assortment of chromosomes and crossing over of alleles between chromatids
• Gametes are unique compared to somatic cells because they are haploid, containing only one copy of each chromosome, while somatic cells are diploid, containing two of each chromosome
• Gametes are formed through a special form of cell division called meiosis, which results in genetically unique cells due to crossing over and independent assortment
• Meiosis occurs in testes and ovaries in animals, as well as anthers and ovaries of flowering plants
• Meiosis I introduces genetic diversity by randomly dividing a cell’s genes in two, resulting in two haploid cells, while Meiosis II separates each duplicated chromosome into its two sister chromatids and places one in each daughter cell, resulting in four haploid gametes
• Independent assortment during meiosis results in a totally random combination of chromosomes after Meiosis I, contributing to genetic diversity within a population
• Crossing over in meiosis occurs during the first meiotic division where homologous chromosomes pair up at the equator and exchange genetic material, leading to a large amount of variation
• Naming Halogenoalkanes:

  • Based on original alkane with a prefix indicating halogen atom: Fluoro for F, Chloro for Cl, Bromo for Br, Iodo for I
• Substituents are listed alphabetically in naming halogenoalkanes
• Halogenoalkanes can be classified as primary, secondary, or tertiary depending on the number of carbon atoms attached to the C-X functional group
• Halogenoalkanes undergo nucleophilic substitution reactions with nucleophiles like :OH-, :NH3, CN-
• The rate of nucleophilic substitution reactions in halogenoalkanes depends on the strength of the C-X bond, with C-F bonds being the strongest and C-I bonds being the weakest
• Hydrolysis of halogenoalkanes with water results in the formation of alcohols and halide ions
• Aqueous silver nitrate can be used to compare the reactivity of different halogenoalkanes by observing the rate of formation of silver halide precipitates
• Nucleophilic substitution with cyanide ions:

  • Change in functional group: halogenoalkane → amine
  • Reagent: NH3 dissolved in ethanol
  • Conditions: Heating under pressure in a sealed tube
  • Mechanism: Nucleophilic substitution
  • Type of reagent: Nucleophile, :NH3
• Elimination reaction of halogenoalkanes:

  • Change in functional group: halogenoalkane → alkene
  • Reagents: Potassium (or sodium) hydroxide
  • Conditions: In ethanol; heat
  • Mechanism: Elimination
  • Type of reagent: Base, :OH-
• Ozone Chemistry:

  • The naturally occurring ozone (O3) layer in the upper atmosphere filters out harmful UV radiation
  • Ozone in the lower atmosphere is a pollutant contributing to smog
  • Man-made chlorofluorocarbons (CFCs) caused a hole in the ozone layer
  • Chlorine radicals formed in the upper atmosphere from C–Cl bonds breaking contribute to ozone depletion