Biology

• Ribosome - The site of protein synthesis
• The nucleus is the control centre of the cell, containing genetic material (DNA) that controls all activities within the cell.
• Heredity is a key feature in cell division and reproduction, involving the passing of chromosomes from parent to daughter cells
• Chromosomes carry genes, which code for traits
• The process of traits being passed down from parents to offspring is called hereditary
• Genetic material is the material that stores genetic information, stored in a molecule of deoxyribonucleic acid (DNA) in a chromosome
• The DNA molecule contains instructions coded as chemical subunits in distinct sequences
• A gene is a distinct sequence of genetic information that codes for a particular trait
• Locus refers to the specific location of a gene on a chromosome
• Chromosomes are found in the nucleus of all eukaryotic cells and vary depending on species
• Chromosomes occur in sets in multicellular organisms, with diploid (2n) having two sets of chromosomes, haploid (n) having half the normal number of chromosomes, and polyploid having three or more sets of chromosomes
• A karyotype is a display of an individual's chromosomes
• Asexual reproduction involves the production of a new individual from a single parent through cell division, resulting in genetically identical daughter cells
• Clones are produced through asexual reproduction, where offspring are genetically identical to the parent
• Cloning oneself can be achieved through binary fission (e.g., bacteria), budding (e.g., jellyfish), or fragmentation (e.g., starfish, worms)
• Advantages of asexual reproduction include no need to find a mate, no energy spent on courtship, and rapid population increase, but disadvantages include the risk of the whole population dying if the environment changes
• Sexual reproduction involves the fusion of two sex cells from different parent organisms, resulting in genetically variable generations
• Hyphae


  Microscopic threads that make up the body of most fungi
• Mycelium


  Tangled mass of hyphae found in soil or organic matter
• Fruiting Bodies


  Reproductive structure that arises from mycelium & produces spores for reproduction
• Hyphae


  • Microscopically thin
  • Structure unlike plant or animal cells
  • Cell wall composed of chitin
  • Cytoplasm is continuous from end to end
• Chitin


  A complex chemical found in the cell walls of fungi and in the external coverings of insects and crustaceans such as lobsters and crabs (polysaccharide or carbohydrate)
• Asexual reproduction of fungi

  When conditions are favourable (ex. moisture & food available)
• Sexual reproduction of fungi

  When conditions are unfavourable (dry, shortage of food)
• Main categories of Fungi

  • Caselike Fungi
  • Saclike Fungi
  • Clublike Fungi
• Caselike Fungi (Phylum: Zygomycota)

  • Terrestrial saprobes
  • Spores in caselike structure: sporangium
  • Hyphae that extend into the food source: rhizoids
• Reproduction of Caselike Fungi

  1. Asexual if favourable conditions

  2. Sexual if unfavourable conditions
• Saclike Fungi (Phylum: Ascomycota)


  • Example: mildew, truffles, some yeasts/moulds
  • Spores in saclike (ascus) structure
• Reproduction of Saclike Fungi

  1. Asexual: spores called conidia

  2. Sexual: produces ascospores, dormant
• Yeast


  • Unicellular, saclike
  • Reproduce by budding (ideal conditions) or ascospores (poor conditions)
  • Can carry out anaerobic respiration
• Yeast


  • Good: baking, beer, wine
  • Bad: infections
• Clublike Fungi (Phylum: Basidiomycota)


  • Example: mushrooms, rusts, smuts, puffballs, bracket fungi
  • Saprobes or parasites (live on decaying organisms)
• Grocery store mushrooms are Clublike Fungi
• Mosquito life cycle of Plasmodium

  1. Mosquito bites infected human and takes up Plasmodium sex cells

  2. Sex cells join and make new individuals of the sexual form of Plasmodium

  3. Sexual form of Plasmodium develops into a structure that produces many copies of the asexual form which are released into the saliva of the mosquito

  4. Mosquito bites another human, releasing the asexual form of Plasmodium into the human

  5. The asexual form of Plasmodium infects liver cells of the human

  6. Asexual form multiples by asexual reproduction, eventually breaking the cell

  7. The asexual form of Plasmodium infects red blood cells and continues to multiply by asexual reproduction