The World of Microorganisms: Friend or Foe? Class 8 Worksheet for FREE
Microorganisms are all around us, and many of them play important roles in our daily lives. From aiding in digestion to harmlessly inhabiting our skin, these microscopic creatures can be both friend and foe. In this class 8 worksheet, students will learn about the various types of microorganisms and their potential benefits and drawbacks.
What are microorganisms?
Microorganisms, also known as microbes, are tiny living organisms that are too small to be seen with the naked eye. They can be found in almost every environment on Earth, including soil, water, air, and even inside other living organisms. While some microorganisms can cause diseases and infections, others play critical roles in maintaining the health of our planet and all living things. Examples of microorganisms include bacteria, viruses, fungi, protozoa and algae. They come in different shapes and sizes and have unique characteristics that help them thrive in their habitats.
OR Microorganisms are tiny living organisms that are invisible to the naked eye, but they are present everywhere in the environment. They can be found in soil, water, air, and even in our bodies. In Class 8 Science, the topic of microorganisms is covered under the chapter "Microorganisms: Friend and Foe". This chapter discusses the various types of microorganisms, their characteristics, and their importance in our daily lives.
One of the most important aspects of microorganisms is that they are beneficial to us in many ways. Friendly microorganisms help in maintaining a healthy ecosystem by decomposing dead matter and recycling nutrients back into the environment. They are also used in the production of various foods and beverages, such as cheese, bread, yogurt, and beer.
In addition, microorganisms are widely used in medicine. They are used in the production of antibiotics, which are essential in treating bacterial infections. They are also used in the development of vaccines to prevent viral diseases like measles and hepatitis.
Apart from their beneficial uses, microorganisms can also be harmful to human health. Cholera, for example, is a waterborne disease caused by the bacterium Vibrio cholerae. Other harmful microorganisms include pathogenic bacteria, viruses, and fungi that cause diseases like tuberculosis, pneumonia, and ringworm.
In the classroom, the topic of microorganisms is covered comprehensively in Class 8 Science. The chapter "Microorganisms: Friend and Foe" covers topics such as the types of microorganisms, their characteristics, their beneficial and harmful uses, and their importance in our daily lives.
To reinforce understanding, worksheets are often provided to students as a tool to test their knowledge. The worksheets cover various aspects of the topic, such as the 10 uses of microorganisms, types of microorganisms, and harmful microorganisms. Additionally, the worksheets also cover topics like the causes and effects of diseases caused by microorganisms, and how to prevent their spread.
In conclusion, microorganisms are an essential part of our environment, and their significance in our daily lives cannot be overstated. They play an important role in food production, medicine, and maintaining a healthy ecosystem. It is crucial to understand the different types of microorganisms, their characteristics, and their uses in our daily lives, and this knowledge is effectively taught in Class 8 Science.
Microorganisms friend and foe class 8 important questions and answers
- What are microorganisms? Name some of the different types of microorganisms.
Answer: Microorganisms are tiny living organisms that are too small to be seen with the naked eye. They include bacteria, viruses, fungi, protozoa, and algae.
- How are microorganisms beneficial to us? Give at least three examples.
Answer: Microorganisms are beneficial to us in many ways. They help in the process of decomposition, they are involved in food production, and they play a role in the nitrogen cycle.
- What are harmful microorganisms? Provide examples of diseases caused by them.
Answer: Harmful microorganisms are those that cause disease in humans, animals, and plants. Examples of diseases caused by harmful microorganisms include cholera, tuberculosis, and malaria.
- Explain how microorganisms are involved in the process of decomposition.
Answer: Microorganisms play a critical role in the process of decomposition by breaking down dead organic matter into simpler substances. Bacteria and fungi are the primary decomposers in the ecosystem.
- What is the difference between pathogenic and non-pathogenic microorganisms?
Answer: Pathogenic microorganisms are those that cause disease in humans, animals, and plants, while non-pathogenic microorganisms do not cause disease.
- What are antibiotics? How do they work against harmful microorganisms?
Answer: Antibiotics are medicines that can kill or slow down the growth of harmful microorganisms. They work by targeting specific parts of the microorganism, such as the cell wall or the DNA.
- Describe the role of microorganisms in food production. Give at least two examples.
Answer: Microorganisms are used in food production to produce products such as cheese, yogurt, and bread. In cheese and yogurt production, bacteria are used to ferment the milk. In bread production, yeast is used to help the dough rise.
- Explain how microorganisms are involved in the nitrogen cycle.
Answer: Microorganisms play a key role in the nitrogen cycle by converting nitrogen gas in the atmosphere into a form that plants can use. Bacteria in the soil and in the roots of legumes convert nitrogen gas into ammonia, which is then converted into nitrites and nitrates by other bacteria.
- What is the difference between bacteria and viruses? Give examples of diseases caused by each.
Answer: Bacteria are single-celled organisms that can reproduce on their own, while viruses are not considered living organisms and require a host cell to reproduce. Examples of bacterial diseases include strep throat and E. coli infections, while examples of viral diseases include influenza and the common cold.
- How can we prevent the spread of harmful microorganisms? Provide at least three ways.
Answer: We can prevent the spread of harmful microorganisms by practicing good hygiene, washing our hands regularly, and avoiding contact with sick individuals. Additionally, vaccines can be used to prevent the spread of certain diseases.
- What is the importance of microorganisms in maintaining a healthy ecosystem?
Answer: Microorganisms play a critical role in maintaining a healthy ecosystem by cycling nutrients, breaking down organic matter, and decomposing dead organisms.
- How do microorganisms play a role in the development of vaccines?
Answer: Microorganisms are used to develop vaccines by exposing the body to a weakened or killed form of a pathogenic microorganism, which triggers an immune response and builds immunity to the disease.
- What is the significance of handwashing in preventing the spread of harmful microorganisms?
Answer: Handwashing is an important way to prevent the spread of harmful microorganisms because it removes dirt and germs from the hands, reducing the likelihood of transmitting bacteria and viruses.
- Explain how the use of pesticides can harm beneficial microorganisms.
Answer: Pesticides can harm beneficial microorganisms by killing them along with the harmful
FAQs
Q: What are microorganisms? A: Microorganisms are tiny living organisms that are too small to be seen with the naked eye. They include bacteria, viruses, fungi, and protozoa.
Q: What is the importance of microorganisms? A: Microorganisms play a vital role in our ecosystem. They are important for the decomposition of organic matter, nutrient cycling, and soil formation. They are also used in food production, biotechnology, and medicine.
Q: What are the types of microorganisms? A: There are four main types of microorganisms - bacteria, viruses, fungi, and protozoa.
Q: What are friendly microorganisms? A: Friendly microorganisms are microorganisms that are beneficial to humans. They help in digestion, food production, and biotechnology.
Q: What are harmful microorganisms? A: Harmful microorganisms are microorganisms that cause disease in humans, animals, and plants. They include bacteria, viruses, and fungi.
Q: What is the difference between bacteria and viruses? A: Bacteria are single-celled organisms that can reproduce on their own, while viruses need a host cell to reproduce. Bacteria can be beneficial or harmful, while viruses are always harmful.
Q: How do microorganisms cause disease? A: Microorganisms cause disease by invading and damaging host cells or by producing toxins that harm the host.
Q: What is cholera and what causes it? A: Cholera is a water-borne disease caused by the bacterium Vibrio cholerae. It causes severe diarrhea and dehydration and can be fatal if left untreated.
Q: How are microorganisms used in food production? A: Microorganisms are used in food production to make products like bread, cheese, yogurt, and beer. They are also used to preserve food by pickling, fermenting, and canning.
Q: How are microorganisms used in biotechnology? A: Microorganisms are used in biotechnology to produce medicines, vaccines, and enzymes. They are also used in genetic engineering and bioremediation.
Q: How do we protect ourselves from harmful microorganisms? A: We can protect ourselves from harmful microorganisms by practicing good hygiene, such as washing our hands regularly, cooking food thoroughly, and avoiding contact with sick people. We can also use vaccines and antibiotics to prevent and treat infections.
