SCIENCE

• ABO system


  Blood group system controlled by multiple alleles (IA, IB, i)
• Blood types

  • A, B, AB, O
• IA and IB

  Dominant alleles
• i

  Recessive allele
• Codominance


  When IA and IB are both inherited, both alleles are expressed
• Female sex chromosome

  XX
• Male sex chromosome

  XY
• Father's sperm carries Y chromosome


  Child is male
• Father's sperm carries X chromosome


  Child is female
• Sex-linked/X-linked traits

  • Occur in sex chromosomes
  • Females can be carriers
  • Males are affected if they inherit faulty X chromosome
• Hemophilia

  Continuous bleeding in joints
• Color blindness


  Inability to recognize specific colors (red and green)
• Duchenne Muscular Dystrophy


  Weakening of muscles, making affected individual unable to walk or stand
• Punnett square


  Used to predict possible genotype of offspring based on parental alleles
• Genotypic ratio


  Number of times a given allele occurs after a cross
• Phenotypic ratio


  Number of times a physical trait is displayed after a cross
• Blood types

  • A and B are dominant alleles
  • O is recessive allele
  • A and B can be homozygous or heterozygous
  • AB is codominant
• ABO blood type is an example of multiple alleles
• Human chromosomes

  • 23 pairs
  • First 22 pairs are autosomes
  • Last pair are sex chromosomes
• Genetics is the branch of biology that studies heredity
• Blood types are inherited
• Sex of child is determined by father's sex chromosome
• Some traits are only present in males or females
• Males are more prone to baldness compared to females
• Some traits are similarly expressed in both sexes
• Non-Mendelian genetics explains multiple alleles and sex-linked traits
• Biodiversity


  Different forms of life in an area
• Community

  All plant and animal populations living together in an area
• Extinct species


  Organisms in which the last member of its species no longer survives
• Endangered species


  Organisms that have a very low population size and may become extinct soon
• Limiting factors


  Things that can limit the population size of certain species
• Population


  All members of a given species that live in a particular location
• Threatened species

  Species that have rapidly decreased in number of individuals
• Sustainable development


  Society should live within the carrying capacity of the environment
• Photosynthesis

  1. Light-dependent reactions

  2. Light-independent reactions
• Light-dependent reactions


  Convert light energy into chemical energy, take place in thylakoid membrane
• Light-independent reactions


  Series of biochemical reactions that convert carbon dioxide and other compounds into glucose, also known as Calvin cycle
• Chloroplast


  Organelles that conduct photosynthesis, contain chlorophyll
• Internal structure of chloroplast

  • Outer membrane
  • Stroma
  • Thylakoid
  • Inner membrane
  • Lamella
  • Granum
• Factors affecting rate of photosynthesis