shit i got wrong

• Why isn't there more than 4-5 trophic levels?

  1. Energy is lost from one trophic level to next

  2. Only 10% of the energy is transferred

  3. Energy is lost by movement and heat

  4. Not parts of organism is eaten

  5. And not all eaten parts are digested
• How is antibiotic resistance obtained?

  1. Mutation causes single bacteria to be resistant to antibiotics

  2. When human is sick they take medicine

  3. Causing all non resistant bacteria to die

  4. Resistant bacteria survives and is able to reproduce

  5. By reproducing they pass resistant gene to offspring
• How are bacteria useful?

  • They allow us to produce large amounts of complex molecules such as insulin
  • This is because bacteria reproduce quickly
  • And don't take up much space
• Pathway of water from outside of root to xylem vessel?

  1. Water enters root hair cell

  2. From high water potential in soil to low water potential in roots

  3. Across semi permeable membrane

  4. Via osmosis
• Hormone


  • Chemical substance secreted by a gland
  • Into the blood
  • Causes changes to body
• How the liver responds to an increase in insulin concentration?

  1. Converts glucose to glycogen

  2. Stores glycogen
• Advantages of breastfeeding


  • Suitable temp
  • Give offspring passive immunity
  • Contains all essential nutrients for child
  • No chance of it being infected
  • No risk of allergic reactions
  • Easy to digest for offspring
• Codominance


  • When 2 dominant alleles are present
  • They both show effect on phenotype
• Allele


  • Different variations of the same gene
  • Due to different dna,base sequence
• What happens to lakes when eutrophication occurs

  1. Fertilizers runoff into lakes

  2. Fertilizer causes algae to grow larger

  3. This lead to them blocked sunlight

  4. Which results in aquatic plants at the bottom photosynthesizing less

  5. Due to less sunlight and dying

  6. This would lead to more decomposers as there is more available food

  7. Which would lead to an increase in oxygen consumption

  8. Because of this the co2 concentration in water would increase

  9. Resulting in fish dying

  10. As they can survive due to lack of o2/high co2
• Role of antibodies in defending the body against shit

  • Antibodies specific to pathogen
  • They bind to its antigen and destroy pathogen
  • They also mark pathogen allowing phagocyte to engulf pathogen