b1

• magnification


  how much larger a displayed object is compared with the original object
• resolution


  the ability to distinguish between two points
• why is staining used?

  • increases constrast
  • some specimens are colourless
  • useful to highlight different structures
• formula to calculate magnification from image size and actual size

  image size = actual size x magnification
• formula to calculate total magnification

  total magnification = eyepiece magnification x objective lens magnification
• how is a light microscope set up?

  1. place the specimen on a slide
  2. cover it with a cover slip
  3. illuminate with a lamp
  4. view using eye piece
• five parts of an animal cell

  • nucleus
  • mitochondria
  • cell membrane
  • cytoplasm
  • ribosomes
• two functions of the nucleus

  • controls the cell
  • contains genetic material - contained in the form of chromosomes
• function of the cytoplasm


  site where most of the cell's reactions take place
• function of the mitochondria


  site of aerobic respiration
• function of ribosomes


  site of protein synthesis
• three organelles found only in plant cells

  • cellulose cell wall
  • permanent vacuole
  • chloroplasts
• what is the function of the permanent vacuole and what does it contain?

  • supports the cell
  • contains cell sap
• function of chloroplasts


  site of photosynthesis
• three differences between prokaryotic and eukaryotic cells

  • prokaryotic cells have no nucleus
  • prokaryotic cells have plasmid loops of dna
  • prokaryotic cells have no mitochondria
• describe the image created by an electron microsope

  • image is black and white
  • 2d or 3d
  • very high magnification and resolution
• why are electron microscopes better than light microscopes?


  they produce images with enough detail to see structures inside cells
• function of a cell wall and what is it made of?

  • provides strength and support
  • made of cellulose
• structure of dna

  • polymer made of many nucleotide monomers
  • made of 2 strands in the shape of a double helix
• structure of a nucleotide

  • a five carbon sugar
  • phosphate group
  • nitrogeneous base
• four bases in dna

  • adenine (a)
  • thymine (t)
  • cytosine (c)
  • guanine (g)
• how do the bases in dna pair up?

  • adenine pairs with thymine,
  • guanine pairs with cytosine.
• describe transcription

  1. dna unzipped
  2. complementary mRNA nucleotides bind and are joined together
  3. mRNA detaches and leaves the nucleus
• decribe translation

  1. mRNA travels to a ribosome
  2. carrier molecules carry amino acids to the ribosome based on the mRNA sequence
  3. the amino acids are joined together
• how does the sequence of dna affect the protein made in protein synthesis?

  dna is a triplet code where three bases code for one amino acid and the order of amino acids determine the protein produced
• what are enzymes?

  enzymes are biological catalysts which speed up the rate of metabolic reactions
• describe the structure of enzymes

  proteins that contain an active site that fits a specific substrate
• describe the lock and key hypothesis

  1. a substrate that fits the active site of an enzyme binds
  2. a reaction occurs (catalysed by the enzyme)
  3. products are released
• four factors that affect enzyme function

  • temperature
  • pH
  • substrate concentration
  • enzyme concentration
• decribe the affect of temperature on the rate of an enzyme-controlled reaction

  1. as the temperature increases, so does the rate of reaction
  2. once the temperature exceeds the optimum, the enzyme denatures and the rate of reaction decreases
• purpose of respiration


  to produce energy in the form of ATP from larger molecules
• what type of reaction is respiration?


  exothermic
• when does aerobic respiration take place?


  when there is plenty of oxygen available
• what is the word equation for aerobic respiration? 


  glucose + oxygen -> carbon dioxide + water
• what is the symbol equation for aerobic equation?

   C6H12O6 + 6O2 -> 6CO2 + 6H2O 
• when does anaerobic respiration take place?


  when there is no oxygen available
• what does anaerobic respiration in animals produce?


  lactic acid and energy
• what does anaerobic respiration in yeast produce?

  ethanol, carbon dioxide and energy
• which type of repiration produces more ATP?

  aerobic respiration which produces 36 ATP compared to anaerobic respiration which produces only 2 ATP
• what is the oxygen debt?


  the extra oxygen that is needed to breakdown the lactic acid produced in anaerobic respiration