bio ch23 Infectious diseases and diseases prevention

• Viruses


  non cellular particles

  nucleic acid surround by protein coat

  eg: influenza

  Dengue fever （蚊

  Measles （麻疹

  HepatitsB（肝

  AIDS
• Bacteria


  unicellular prokaryotes

  capsule

  causing diseases by relasing toxins

  eg: cholea（肚痾
• Protists


  eukaryotes, unicellular

  no cell wall

  parasites

  eg : Malaria（瘧疾
• Fungi


  eukaryotes, unicelluar, moulds

  eg: yeast, athlete's foot（hk腳

  spores for reproduction

  secrete enzyme to digest humans tissue

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• Ways of transmission and preventive measures

  by droplet of water

  (cover mouth w tissue pp when coughing n sneezing

  face mask

  wash hands

  x crowd places)

  
  

  by water or food

  (cook thoroughly, wash hands, temp, separate raw/cooked)

  
  

  by vectors

  Animal that carries n transfer the pathogen to the host

  (rodent老鼠🐭mosquito蚊 ,

  
  

  by body fluids

  eg: blood semen vaginal secretion

  (wear gloves , condom)

  
  

  by direct contact

  (maintain gd personal hygiene)

  ​
• indiscriminate use of antibiobics

  eg: taking anti unnecessary whe hav viral infections

  not completing a complete course of anti

  
  

  antibiotics resistance!

  
  

  ways to ease:

  reduce the exposure of bacteria to anti

  ensure all the pathogenic bacteria are killed

  develp new drugs to reduce the use of anti

  ​
• sulpha drugs


  enzyme inhibitors
• action of antibiotics

  prevent the formation of cell wall to inhibit the growth

  breaking down cell membranes

  inhibit the dna synthesis
• antibiotic resistance

  there are genetic variations among bacteria in anti resistant due to mutation

  when an anti is used, the resistant bacteria hv a higher chance to survive n repro

  when anti are indiscriminately use, the proportion of resistant bac in the population increa in subsequent generation
• experiment question ( agar plate)

  agar plate

  q: Why temp should be 37°C

  a: stimulates the human body temp, to find out the effectiveness of anti in patient
• experiment question (agar plate)

  controlled variable

  
  

  independent variable

  
  

  dependent variable

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