Foundations in Biology - ALL NOTES

• What is the formula for percentage change?

  Percentage change = change/initial x 100
• How is cardiac output calculated?

  Cardiac output = heart rate x stroke volume
• What is the formula for magnification?

  Magnification = image size/actual size

  
• What are the key differences between magnification and resolution in microscopy?

  • Magnification: Size of the image vs. real object
  • Resolution: Ability to distinguish close objects
• What are the types of microscopes and their basic functions?

  • Optical Light Microscopes: Use light to form images
  • Electron Microscopes: Use electrons to form images
  • Transmission Electron Microscope: Passes electrons through samples
  • Scanning Electron Microscope: Scans surface with electrons
  • Laser Scanning Confocal Microscope: Uses laser and fluorescent dyes
• What is the maximum resolution of an optical light microscope?

  Maximum Resolution = 0.2 micrometres
• What is the maximum resolution of a transmission electron microscope?

  Maximum Resolution = 0.0002 micrometres
• What is the maximum useful magnification of a light microscope?

  Maximum useful magnification = x1500
• What is the maximum useful magnification of a scanning electron microscope?

  Maximum useful magnification = x1,500,000
• What can be observed using an optical light microscope?

  Small organelles like ribosomes and lysosomes
• What are the advantages of optical light microscopes?

  Small, easy to carry, no vacuum needed
• What are the disadvantages of electron microscopes?

  Large, requires vacuum, specimens are dead
• What are the advantages and disadvantages of transmission electron microscopes (TEMs) and scanning electron microscopes (SEMs)?

  Advantages of TEMs:

  • High resolution images
  • Internal structures visible

  
  

  Disadvantages of TEMs:

  • Only thin specimens
  • Cannot observe live specimens

  
  

  Advantages of SEMs:

  • Can be used on thick specimens
  • 3D structures observed

  
  

  Disadvantages of SEMs:

  • Lower resolution than TEMs
  • Cannot observe live specimens
• What is the diameter of eukaryotic cells?

  20 micrometres or more
• What is the function of the cell surface membrane?

  Controls exchange of materials in and out
• What is the structure of the cell surface membrane?

  Formed from a phospholipid bilayer
• What is the function of the nucleus?

  Contains chromatin and makes chromosomes

  
• What is the role of the nucleolus?

  Site of ribosome production
• What is the function of mitochondria?

  Site of aerobic respiration
• What is the structure of mitochondria?

  Surrounded by double membrane with cristae

  
• What is the function of chloroplasts?

  Site of photosynthesis in plant cells
• Where are ribosomes found?

  In cytoplasm or rough endoplasmic reticulum

  
• What is the function of the rough endoplasmic reticulum?

  Processes proteins made by ribosomes

  
• What is the function of the smooth endoplasmic reticulum?

  Involved in lipid and carbohydrate synthesis

  
• What is the function of the Golgi apparatus?

  Modifies and packages proteins and lipids

  
• What is the role of lysosomes?

  Breaks down waste materials and used in apoptosis
• What are centrioles made of?

  Hollow fibres made of microtubules
• What is the function of microtubules?

  Provides support and movement of the cell
• What are microvilli?

  Cell membrane projections that increase surface area
• What is the function of cilia?

  Allows movement of substances over the cell surface
• What is the function of flagella?

  Provides cell movement
• What are plasmids?

  Small loops of DNA separate from main DNA
• What is the function of the slime capsule in prokaryotes?

  Protects bacteria from drying out and immune attack
• What are the organelles involved in protein synthesis?

  • Nucleus
  • Ribosomes
  • Rough endoplasmic reticulum
  • Golgi apparatus
  • Cell surface membrane

  
• What are the steps in protein production?

  1. Nucleus manufactures mRNA
  2. mRNA leaves nucleus through nuclear pore
  3. mRNA attaches to ribosome
  4. RER processes proteins sent in vesicles to Golgi
  5. Vesicles fuse with Golgi apparatus
  6. Golgi processes and packages proteins
  7. Vesicles fuse with cell membrane to secrete proteins

  
• What is a light microscope?

  A microscope using lenses to magnify visible light
• What is a transmission electron microscope (TEM)?

  A microscope that passes electrons through a sample

  
• What is a scanning electron microscope (SEM)?

  A microscope that scans surface with electrons

  
• What is the definition of magnification?

  How much bigger an image appears than the original
• What is the definition of resolution?

  The ability to distinguish two different points