Sexual Reproduction

• Sexual reproduction 


  is a process involving the fusion of nuclei of two gametes to form a zygote. It produces genetically dissimilar offspring.
• Meiosis


  • a type of cell division that gives rise to genetically dissimilar cells in which the chromosome number is halved due to the separation of homologous chromosomes
  • Haploid gametes are produced
  • Genetically dissimilar gametes are produced.
• Homologous Chromosomes

  • One chromosome from each parent

  • Same shape

  • Same size

  • Same sequence of genes
• Haploid and Diploid


  • Haploid has one set of chromosomes
  • Diploid has two sets of chromosomes

  
• Advantages of Sexual Reproduction

  • Offspring may inherit beneficial qualitites
  • Genetic variation

  
• Sexual vs Asexual Reproduction

  
• Disadvantages of Sexual Reproduction

  • Two parents needed
  • Fusion of nuclei of gametes needed
  • Slower than asexual reproduction

  
• Plant Tissue Culture


  • Under sterile conditions (so that mould and bacteria will not grow on nutrient agar)
  • Plantlet placed on nutrient agar in a petri dish
  • Pros :

  1. High quantity in shorter time than traditional farming
  2. Controlled environment -> High yield
  3. Conservation of endangered species

  • Cons :

  1. Genetically identical -> Wiped out if conditions change/infection
  2. Expensive -> Labour (skilled workers needed) and lab resources
  3. Decrease biodiversity