Life Processes of Microorganisms

Microorganisms are living things that can be found around us. This chapter will explain more on the types of microorganisms, harmful effects of microorganisms and uses of microorganisms.
3.1  Life Processes of Microorganisms
Microorganisms are living things that cannot be seen with the naked eye and can only be seen using a microscope and a magnifying glass. There are several types of microorganisms and these living things also carry out life processes like other living things.
  Microorganisms are tiny living things that cannot be seen with the naked eyes  


Examples: Yeast, mucor, penicillium, mould
Characteristics: Only mould can be seen with the naked eye, can be found on bread, rice and some types of fruits



Examples: Ameoba, paramecium
Characteristics: The habitat of protozoa are ponds, lakes and rivers (live in places where there is water)



Examples: Bacillus, salmonella, streptococcus, E.Coli
Characteristics: Exist in many shapes, sizes and colors, can be found in the air, soil, water, food and in the body of living or dead organisms



Examples: HIV, Influenza virus
Characteristics: The tiniest microorganisms. Viruses can only be seen under an electron microscope



Examples: Spirogyra, phytoplankton
Characteristics: Have the charateristics of plants. Enable to make their own food through the process of photosynthesis

Life Process of Microorganisms


  • Microorganisms use oxygen to breathe and produce carbon dioxide


  • Microorganisms move in different ways


  • Microorganisms undergo a growing process
  • Example: mold on bread

Growth of Microbes

  • The growth of microorganisms requires water, air, temperature, nutrients and acidity

Useful and harmful microorganisms

  • Some of the microorganisms are beneficial to living things and some are harmful to living things.
Harmful Effects Explanation
Spoil food
  • Causes changes in texture, appearance, smell and taste
  • Will experience food poisoning, diarrhea and pain if ingested spoilt food
Contagious diseases
  • Conjunctivitis
  • Ringworm
  • White spots
  • Scabies
  • Smallpox
Tooth decay
  • Bacteria that is found in the mouth acts on the bits of food by changing the sugar and starch in the food into acid
Food Poisoning
  • Bacteria will reproduce and produce toxin in the instestines
  • Symptoms: diarrhea, vomiting, dizziness
Uses of Microorganisms
Types of Microorganisms Uses
  • Cheese
  • Yogurt
  • Fermented soybean
  • Bread
  • Fermented rice
  • Production of antibiotics and vaccines
Bacteria dan fungi
  • Decomposition of organic substances

Live healthily according to the knowledge of microorganisms

  • Contagious diseases caused by the spread of microorganisms can be prevented by practicing healthy daily practices.

Contagious diseases can be spreaded through:

  • Food and drinks
  • Sneezing and coughing
  • Carrier animals such as flies and mosquitoes
  • Touch

Healthy daily routines include:

  • Washing hands before eating and after coming out from the toilet
  • Covering the mouth when sneezing or coughing
  • The place where food is prepared must be in clean condition
  • Drink boiled water and eat food that is cooked properly