Microbes Friend and Foe in One Shot | Biology - Class 8th | Umang | Physics Wallah
Physics Wallah Foundation・59 minutes read
Microbes are tiny organisms found everywhere, including bacteria, fungi, and viruses, each with unique functions like producing antibiotics and causing illness. Understanding the interaction of viruses with host cells is crucial for comprehending their impact on health and disease.
Insights
- Viruses, despite not being considered living organisms, can infect cells by injecting their DNA, causing illness, highlighting their unique behavior compared to other microbes.
- Microbes, including bacteria, fungi, and viruses, play diverse and essential roles in nature, such as producing antibiotics, curdling milk proteins, and breaking down carbohydrates for fermentation, showcasing their significance in various biological processes.
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Recent questions
What are microbes?
Microbes are small organisms found everywhere.
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Summary
00:00
Microbes: Small Organisms with Big Impacts
- Microbes are unicellular and multicellular organisms that are very small in size and often invisible to the naked eye.
- Microscopic organisms, known as microbes, are omnipresent and can be found everywhere, including in the air, water, and soil.
- Microbes include various categories such as bacteria, algae, and protozoa, each with distinct characteristics and functions.
- Fungi, like bread mold and Penicillium, are examples of microbes that play essential roles, such as producing antibiotics like Penicillin.
- Viruses, although not considered living organisms due to their lack of cells, consist of protein and nucleic acid, either DNA or RNA.
- The genetic material of viruses, DNA or RNA, is crucial for passing on information and influencing cellular functions.
- Viruses infect cells by attaching to them and injecting their DNA, causing the host cell to replicate the virus and potentially leading to illness.
- Understanding the structure and function of viruses, including their interaction with host cells, is essential in comprehending their impact on health and disease.
- The intricate relationship between viruses and cells highlights the unique mechanisms through which viruses operate and affect biological systems.
- Exploring the complexities of microbes, including bacteria, fungi, and viruses, sheds light on their diverse roles in nature and their significance in various biological processes.
19:48
Microbes: From Illness to Immunity
- Gradual illness onset leads to virus entering cell and attaching to DNA
- Virus instructs cell to produce more viruses, causing sickness
- Unique virus behavior compared to other microbes
- Friendly and harmful microbe examples like curd bacteria causing sickness
- Lactobacillus bacteria in curd converts lactose to lactic acid
- Lactic acid curdles milk proteins, forming curd
- Yeast in bread fermentation breaks down carbohydrates to produce energy and carbon dioxide
- Carbon dioxide causes bread to rise and become fluffy
- Microbes produce alcohol, vinegar, and antibiotics commercially
- Vaccination introduces weak virus to build immunity against stronger viruses like Covid-19
38:32
Microbes, Vaccination, and Disease: A Summary
- Vaccination involves introducing a virus into the body to trigger the production of antibodies, a process initiated by Sir Edward Jenner during a smallpox outbreak.
- Jenner observed that individuals with cowpox, a virus common in Asian countries, were immune to smallpox, leading him to develop the concept of vaccination.
- Microbes, including algae, play a crucial role in photosynthesis, releasing oxygen into the environment and maintaining soil fertility.
- Soil fertility is essential for plant growth, with microbes like cyanobacteria fixing nitrogen and sulfur bacteria supplying sulfur to the soil.
- Decomposers, such as saprophytic organisms, break down organic matter in the soil, while non-decomposable substances like plastic contribute to environmental pollution.
- Diseases caused by microbes can be communicable, spreading from person to person, or non-communicable, arising from internal factors like diet and lifestyle.
- Communicable diseases are transmitted through vectors like mosquitoes, which carry viruses like dengue and malaria from one person to another.
- Vectors like mosquitoes can spread diseases without being affected themselves, highlighting the importance of controlling their populations to prevent outbreaks.
57:47
Microbes, Mosquitoes, and Food Safety: A Summary
- Mosquitoes are important vectors for spreading microbes from one organism to another, such as in the case of malaria.
- Malaria is caused by the Plasmodium protozoa, which is transmitted by Anopheles mosquitoes.
- Plasmodium enters the mosquito's body when it grows in water and remains there until the mosquito infects a human.
- When a mosquito carrying Plasmodium bites a human, the parasite enters the bloodstream, causing damage to blood and liver cells.
- Tuberculosis (TB) is caused by the bacterium Mycobacterium, transmitted through the air when infected individuals sneeze.
- Cholera and typhoid, caused by bacteria, are transmitted through impure water and food, emphasizing the importance of proper hygiene and clean water.
- Hepatitis B, a liver disease caused by a virus, can be prevented through vaccination and boiling water.
- Preventive measures against mosquito-borne diseases like malaria include using mosquito repellents, nets, and keeping surroundings clean to prevent mosquito breeding.
- Food poisoning occurs due to toxins produced by microbes in spoiled food, leading to illness and potentially fatal consequences.
- Food preservation methods involve using chemicals like salt, sugar, and edible oil, as well as heat and cold treatments to inhibit microbial growth and ensure food safety.
01:14:33
Food Preservation and Nitrogen Fixation Processes
- The process of heating and quickly cooling food to destroy microbes is known as pasteurization, named after Louis Pasteur.
- Dry fruits like almonds are preserved by drying them in the sun and storing them in airtight packets in the fridge.
- Nitrogen fixation is the process where bacteria convert atmospheric nitrogen into an organic form, like nitrate and nitrite, beneficial for leguminous plants.
- Leguminous plants form a symbiotic relationship with Rhizobium bacteria in root nodules, allowing them to fix atmospheric nitrogen for plant growth.
- The nitrogen cycle involves lightning and bacteria fixing atmospheric nitrogen, which is then used by plants, animals, and eventually returned to the soil through decomposition, completing a continuous cycle known as nitrification.
