difficult questions

• how is it an advantage for a plant to have very few stomata on the top of the leaf

  less water lost so will not wilt
• describe how water moves from roots to leaves

  by transpiration stream in xylem
• what is translocation and why is it important to plants

  movement of dissolved sugars by the phloem. sugars are made in leaves so need to be transported to other parts of the leaf for respiration or storage
• how would the method of blotting cause errors in the results

  variable amount of water is removed
• why would a scientist use more than one sample size

  more reliable and representative so a mean can be calculated
• why is percentage change in mass better than just in grams

  varied starting points and allows comparisons
• why is active transport necessary in root hair cells

  for movement of minerals against the concentration gradient
• explain why single celled organisms do not need complex structures for gas exchange

  cell shave larger surface area to volume ratio and shorter diffusion path via cell membrane is good enough
• why is it necessary to absorb some food molecules via active transport

  against a concentration gradient
• how can we study how many stomata open with light microscope

  mount epidermis on a slide and count stomata in 5 areas, repeat on other side and calculate mean
• how could a gardener identify the pathogen infecting plants


  compare on a website or send to lab for testing
• what are some uses for monoclonal antibodies


  attaching to radioactive material, drugs and fluorescent proteins to target specific antigens
• how is glucose from the small intestine moved into a muscle cell


  glucose is absorbed by diffusion into blood stream and is delivered to muscles by capillaries
• compare anaerobic respiration in a yeast cell and muscle cell

  anaerobic respiration in yeast cell: produces lactic acid

  muscle cell: produces ethanol

  yeast cell: produces co2

  muscle cell: does not produce co2