Exam questions- Common + struggle questions

• State to uses of genetic fingerprinting

  medical diagnosis and forensic work.
• Suggest two reasons why the theoretical numbers of DNA fragments shown in table 2 are unlikely to be achieved.

  -not enough primers

  -not enough nucleotides
• Describe what happens in the photo lysis of water:

  • The formation of hydrogen ions , electrons and oxygen
  • Electrons accepted into photosystem
• Describe how NADP is reduced in light dependent reaction of photosynthesis;

  • Electrons from photolysis are used to reduce NADP
• Viruses are acellular because they contain no cellular organelles and are not capable of metabolism.
• Viruses are considered non-living because they do not reproduce independently.
• antibiotics are not effective against viruses as viruses do not bacterial enzymes , carry out metabolic processes or contain ribosomes.
• Why is it important for xylem to be open as a continuous tube?

  1. allows unbroken water column
  2. cohesion from hydrogen bonds between water
  3. evaporation causes tension.
• why would damaging the cells lining in the ileum reduce absorption?

  1. reduces surface area
  2. decrease water potential
  3. so water moves out of cells by osmosis
• if asked about separating chromatography say thin layer chromatography or paper chromatography