foundation in biology module 2

• Prokaryotic and Eukaryotic Cells

  • Both contain organelles
  • Cell surface made of phospholipid bilayer
  • Bilayer controls passage of substances
• Prokaryotic organisms


  • Bacteria
• Eukaryotic organisms


  • Animals
  • Plants
  • Fungi
  • Algae
• Prokaryotic cells


  Single-celled, smaller, less complex, do not have membrane-bound organelles
• Eukaryotic cells


  Complex, larger, have membrane-bound organelles
• Prokaryotic cell division


  Binary fission
• Eukaryotic cell division


  1. Mitosis

  2. Meiosis
• Nucleus


  Controls the actions of the cell
• Nucleolus


  Site at which ribosomes are made
• Nucleoplasm


  Semi-solid fluid inside the nucleolus
• Mitochondria


  Produces adenosine triphosphate (ATP) via aerobic respiration
• Mitochondria


  • Oval-shaped
  • Double-membrane organelles
  • Have their own ribosomes and DNA
• Chloroplasts


  Site of photosynthesis, have their own DNA and ribosomes
• Chloroplast structure


  • Inner and outer membranes
  • Thylakoids
  • Grana
  • Stroma
• Golgi apparatus


  Sorts, packages, and tags proteins and lipids
• Golgi vesicles


  • Membrane-bound, fluid-filled vesicles
  • Store and transport modified proteins and lipids
• Lysosomes


  Special type of Golgi vesicles containing enzymes called lysozymes
• Ribosomes


  In charge of protein synthesis
• Endoplasmic Reticulum (ER)


  • Series of interconnected membranous sacs and tubules
  • Rough ER has ribosomes, Smooth ER does not
• Plasma membrane


  Partially permeable barrier between the cell's interior and its surroundings
• Cell wall


  • Rigid covering that protects the cell
  • Found in plants, algae, and fungi
  • Major organic molecule in fungal cell walls is chitin
• Fluid mosaic model


  Describes the structure of plasma membranes
• Cytoskeleton


  • Maintains cell shape
  • Secures organelles
  • Allows movement of cytoplasm and vesicles
• Types of cytoskeletal fibers

  • Microfilaments
  • Intermediate filaments
  • Microtubules
• Centrioles


  Play an important role in cellular division and organization
• Flagella and Cilia


  • Hair-like structures
  • Eukaryotic flagella have a nine-plus-two arrangement
  • Bacterial flagella are helical
• Magnification


  The process of enlarging an object in appearance
• Resolution


  The ability of a microscope to distinguish two adjacent structures as separate
• Optical microscope


  • Maximum resolution is 0.2 micrometres
  • Maximum magnification is around x1500
• Electron microscope


  • Uses a beam of electrons
  • Higher magnification and resolving power than light microscopes
• Scanning Electron Microscope (SEM)

  • Creates details of cell surface characteristics
  • Specimens do not have to be thin
• Transmission Electron Microscope (TEM)

  • Provides details of a cell's internal structure
  • High resolution
• Elements found in carbohydrates

  • Carbon
  • Oxygen
  • Hydrogen
• Elements in lipids


  • Carbon
  • Hydrogen
  • Oxygen
  • OIL
• Elements found in proteins

  • Carbon
  • Sulfur
  • Oxygen
  • Hydrogen
  • Nitrogen
• Elements found in nitric acids

  • Carbon
  • Hydrogen
  • Oxygen
  • Nitrogen
  • Phosphorus
• Water is one of the most useful molecules for life
• Functions of water


  • As a reactant in cells like photosynthesis
  • Provide structural support in cells
  • Keeps organisms cool to maintain an optimum body temperature
• Properties of water


  • Metabolic importance
  • High heat capacity
  • High heat of vaporisation
  • Cohesive properties
  • Useful as a solvent
• Water is a major component of cells and makes up 60-70% of the human body