4. Dorman microorganism…. Dormant means inactive because growth and metabolic processes temporarily stopped. ( dormant – tidakaktifkeranapertumbuhandanprosesmetabolikberhentisecarasementara.) They may dormant until condition are suitable for them to grow and reproduce
5. Why the milk curdled after 3 days? Milk is rich with nutrient like protein. Some bacteria use this nutrients to grow and multiply. As they grow, they may damage the constituent of milk such as protein.
6. Condition of milk after day 3 Day 1 Day 3 The growth of microorganism spoil the milk
7. So what can you conclude about the growth of microorganism?
8.
9. Factors that affect the growth of microorganism Nutrient Humidity (kelembapan) Light (cahaya) Temperature (suhu) pH
10. Nutrient Microorganism need energy for their life… Why? They need energy for growth and reproduce (membesardanmembiak)
11. Nutrients that needed by microorganism Starch kanji Amino acids asid amino Fats lemak Glucose glukosa Inorganic compound sebatianbukanorganik This nutrient supply (bekal) energy to microorganism
18. HUMIDITY Almost all microorganism live in damp or watery habitats They need water to stay alive. What happen when there is no water? Microorganism would be inactive and dead. Moisture content between 25% to 40% is suitable for microorganism to carry out their normal activity.
19. Bacteria in a dry condition They will become a spores and become inactive. That spores can survive with a dry condition. The spores would become active again when moisture is available.
27. LIGHT for algae Some microorganism such algae can live where is an enough light.. Why they need light? They need light to conduct photosynthesis What happen if there is not enough light for algae? Can’t produce food then die
28. UV light The sun is the powerful source of UV light….
29. Light for viruses, bacteria, and fungi They can live with or without light. Why? Because they did not conduct photosynthesis But, some bacteria and fungi are grow better in a adark condition. Uv rays in sunlight could affect the growth rate of microorganism or even kill them.
30. hospitals and food shops employ the use of UV (ultraviolet) light to aid in killing microorganisms, specifically bacteria and mold Preventing infection and the spread of airborne diseases is the goal of hospitals. Food shops aim to keep their food products and preparation surfaces free of bacteria and mold spores. UV light can also be used to purify water.
32. Temperature Suitable temperature for microorganism : 35 º - 40 ºC. This is the optimum temperature for them to growth. 0 ºC microorganism will be inactive.. But there are some bacteria that are still active when the temperature is below 0 ºC. When the temperature are more than 50 ºC, microorganism will form spores and can survive until 120 ºC
36. pH Each kind of microorganism is active at a particular pH value. Setiapmicroorganismaadalahaktifpada pH tertentu Neutral pH (7) is the most suitable for microorganism. The pH value which is too high or low could prevent the growth of microorganism
