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    • Posted by Anup Singh 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 1 answers

    Namratha Rao 3 years, 2 months ago

    Ameba are found in ponds and lakes

    0Thank You

    ANSWER

    • Posted by Chandan Kumar 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 4 answers

    Rajni Maheshwari 3 years, 3 months ago

    Penicilline

    0Thank You

    Anup Singh 3 years, 3 months ago

    Penicilline

    1Thank You

    Kavya Dixit 3 years, 3 months ago

    Penicillin

    0Thank You

    Khushee Bhogayta 3 years, 3 months ago

    Penicillin

    0Thank You

    ANSWER

    • Posted by Sumana Sumana Reddy 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 2 answers

    Sia ? 3 years, 3 months ago

    A) Because carpooling reduces the number of automobiles needed by travelers, it is often associated with numerous societal benefits including: 1) reductions in energy consumption and emissions, 2) congestion mitigation, and 3) reduced parking infrastructure demand

    B) Roadways

    C) Reduce products that require fossil fuel resources to produce. By avoiding paper or plastic shopping bags, you can reduce the demand on the production process, which is fossil-fuel intensive.

    3Thank You

    Rajni Maheshwari 3 years, 3 months ago

    A because car pulling reduce the number of automobile needed by travelerrs

    3Thank You

    ANSWER

    • Posted by Sinchana Hegde 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 1 answers

    Ananya Sharma 3 years, 3 months ago

    The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons. The best-known silk is obtained from the cocoons of the larvae of the mulberry silkworm Bombyx mori reared in captivity (sericulture).

    0Thank You

    ANSWER

    • Posted by Lovepreet Singh 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 0 answers
    ANSWER

    • Posted by Raghav Narayan Nagal 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 1 answers

    Rongli Yeswanth Pandu 3 years, 3 months ago

    Hi

    0Thank You

    ANSWER

    • Posted by Janvi Patel 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 3 answers

    Sia ? 3 years, 3 months ago

    Natural fibers or natural fibres (see spelling differences) are fibers that are produced by geological processes, or from the bodies of plants or animals.

    1Thank You

    V . 3 years, 3 months ago

    the fibres that are obtained from either plants or animals/from nature are known as natural fibres

    0Thank You

    Rajni Maheshwari 3 years, 3 months ago

    Natural fibres are those who are obtained from plants

    0Thank You

    ANSWER

    • Posted by Aryan Pradhan 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 2 answers

    Sia ? 3 years, 3 months ago

    Spontaneous combustion or spontaneous ignition is a type of combustion which occurs by self-heating, followed by thermal runaway and finally, autoignition.

    0Thank You

    Karthik Lc 3 years, 3 months ago

    Spontaneous combustion or spontaneous ignition is a type of combustion which occurs by self-heating, followed by thermal runaway and finally, autoignition.

    0Thank You

    ANSWER

    • Posted by Abhishek Ola 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 1 answers

    Kavya Dixit 3 years, 3 months ago

    The reactivity series is a series of metals, in order of reactivity from highest to lowest. It is used to determine the products of single displacement reactions, whereby metal A will replace another metal B in a solution if A is higher in the series.

    0Thank You

    ANSWER

    • Posted by Kavya Dixit 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 3 answers

    Khushee Bhogayta 3 years, 3 months ago

    U can see in this application itself

    1Thank You

    Kavya Dixit 3 years, 3 months ago

    Reply fast

    0Thank You

    Kavya Dixit 3 years, 3 months ago

    Can anyone please help me

    4Thank You

    ANSWER

    • Posted by Dinesh Dhanushkodi .B 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 1 answers

    Dinesh Dhanushkodi .B 3 years, 3 months ago

    Reply fast

    1Thank You

    ANSWER

    • Posted by Vedansh Sahu 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 1 answers

    Urvashi Sharma ?? 3 years, 3 months ago

    None of above i am not sure

    1Thank You

    ANSWER

    • Posted by Lucky Kumar 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 3 answers

    Kavya Dixit 3 years, 3 months ago

    Liquefied petroleum gas , compressed natural gas , piped natural gas

    0Thank You

    Urvashi Sharma ?? 3 years, 3 months ago

    LPG - Liquified petroleum gas CNG - Compressed natural gas PNG - piped natural gas Ok anyone questions??

    1Thank You

    Lucky Kumar 3 years, 3 months ago

    Liquified petroleum gas, compressed natural gas,piped natural gas

    2Thank You

    ANSWER

    • Posted by Gbs Reddy 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 0 answers
    ANSWER

    • Posted by Divya Sp 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 5 answers

    Ananya Sharma 3 years, 3 months ago

    Hii

    0Thank You

    Kavya Dixit 3 years, 3 months ago

    Hii

    0Thank You

    Vidhi Kapoor 3 years, 3 months ago

    Hi

    1Thank You

    Atamjit Singh 3 years, 3 months ago

    The process of filtering something

    2Thank You

    Abhinish Kumar 3 years, 3 months ago

    What is filtration

    2Thank You

    ANSWER

    • Posted by Abhinish Kumar 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 1 answers

    Lovepreet Singh 3 years, 3 months ago

    Purification of Liquid

    0Thank You

    ANSWER

    • Posted by Kavya Dixit 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 5 answers

    Kavya Dixit 3 years, 3 months ago

    Hii Divya You are from which state and which city

    2Thank You

    Divya Sp 3 years, 3 months ago

    Yes I am Divya sp class 8

    3Thank You

    Divya Sp 3 years, 3 months ago

    Yes

    1Thank You

    Archit Deore 3 years, 3 months ago

    No

    0Thank You

    Archana Yadav Yadav 3 years, 3 months ago

    No

    0Thank You

    ANSWER

    • Posted by Kavya Dixit 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 0 answers
    ANSWER

    • Posted by Abhi Nav 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 4 answers

    Kavya Dixit 3 years, 3 months ago

    The process of loss of water from the leaves of the plants is known as transpiration .

    1Thank You

    Sachin Singh 3 years, 3 months ago

    Gfd

    0Thank You

    Pruthvi . 3 years, 3 months ago

    The process of loss of water is called transpiration.

    1Thank You

    Pragya Kumari 3 years, 3 months ago

    Transpiration is the process of water movement through a plant and its evaporation from aerial parts , such as leaves , stems and flowers .

    2Thank You

    ANSWER

    • Posted by Nikhil Krishna Singh 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 1 answers

    Kavya Dixit 3 years, 3 months ago

    (a) Static Friction : The force of friction called into play , which does not allow two bodies to slide upon one another is called static friction. (b) Sliding friction : The force of friction acting between two bodies , when they are sliding upon one another with a uniform speed is called dynamic friction or sliding friction .

    0Thank You

    ANSWER

    • Posted by Indhraadeptha Av 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 1 answers

    Priyanshu Raj 3 years, 3 months ago

    Hydrogen

    1Thank You

    ANSWER

    • Posted by Rabindra Behera 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 1 answers

    Ankit Yadav 3 years, 3 months ago

    Release hydrogen

    0Thank You

    ANSWER

    • Posted by Harshit Kumar 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 1 answers

    Pruthvi . 3 years, 3 months ago

    As soon as these ingredients are stirred together, enzymes in the yeast and the flour cause large starch molecules to break down into simple sugars. The yeast metabolizes these simple sugars and exudes a liquid that releases carbon dioxide and ethyl alcohol into existing air bubbles in the dough.

    2Thank You

    ANSWER

    • Posted by Shreya Dubey 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 5 answers

    Ananya Sharma 3 years, 3 months ago

    Polio

    1Thank You

    Kavya Dixit 3 years, 3 months ago

    Polio is given to the new born baby

    1Thank You

    Indhraadeptha Av 3 years, 3 months ago

    Polio

    1Thank You

    Rajni Maheshwari 3 years, 3 months ago

    Polio is given to the baby because it effects to defeat with diseases

    1Thank You

    Rohit Kuklare 3 years, 3 months ago

    Polio

    2Thank You

    ANSWER

    • Posted by Komal Raskar 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 2 answers

    Ritik Vats 3 years, 3 months ago

    Chapter 1 question and answer

    2Thank You

    Nishid Gahane 3 years, 3 months ago

    Coal mine is a mine where coal is dig out from earth ?

    3Thank You

    ANSWER

    • Posted by Divanshi Bhuriya 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 1 answers

    Aafiya Naik 3 years, 3 months ago

    Living’ is something that is alive, something that can grow, move, reproduce, respire and carry out various cellular activities.

    3Thank You

    ANSWER

    • Posted by Akash Kumar 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 4 answers

    Pruthvi . 3 years, 3 months ago

    Falling of any thing in earth For ex. 1.falling of ball 2 falling of Book, tea cup

    1Thank You

    Nikhil Krishna Singh 3 years, 3 months ago

    Attraction of meteoroid/asteroid towards earth surface.

    1Thank You

    Rajni Maheshwari 3 years, 3 months ago

    Falling of an apple and falling of a metoride on earth

    1Thank You

    Sneha Nagar 3 years, 3 months ago

    Aroplane ,our body, by we are saikalling,

    1Thank You

    ANSWER

    • Posted by Praval Talwar 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 3 answers

    Rajni Maheshwari 3 years, 3 months ago

    Nitrogen hydrogen chlorine

    1Thank You

    Khushi Rawat 3 years, 3 months ago

    Non metals are nitrogen, hydrogen , chlorine etc

    1Thank You

    Khushi Rawat 3 years, 3 months ago

    Metals are aluminium, copper, zinc etc

    1Thank You

    ANSWER

    • Posted by Aditi Patil 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 1 answers

    Khushi Rawat 3 years, 3 months ago

    Aids is caused by the human immunodeficiency virus. You can get HIV from contact with infected blood, semen, or vaginal fluids.

    1Thank You

    ANSWER

    • Posted by *Armaan Siddiqui 3 years, 3 months ago

    CBSE > Class 08 > Science
    • 2 answers

    Rajni Maheshwari 3 years, 3 months ago

    Exercise Questions (1)fill in the blanks (a) Microorganisms can be seen with the help of a ____________. (b)Blue green algae fix __________ directly from air and enhance fertility of soil. (c) Alcohol is produced with the help of _____________. (d)Cholera is caused by ____________. Solutions:a-microscope b-Nitrogen c-yeast d-bacteria

    2Thank You

    Khushi Rawat 3 years, 3 months ago

    Exercise Questions 1. Fill in the blanks. (a) Microorganisms can be seen with the help of a ____________. (b) Blue green algae fix __________ directly from air and enhance fertility of soil. (c) Alcohol is produced with the help of __________. (d) Cholera is caused by __________. Soln: a) Microscope b) Nitrogen c) Yeast d) Bacteria- Vibrio cholera 2. Tick the correct answer. (a) Yeast is used in the production of (i) sugar (ii) alcohol (iii) hydrochloric acid (iv) oxygen (b) The following is an antibiotic (i) Sodium bicarbonate (ii) Streptomycin (iii) Alcohol (iv) Yeast (c) Carrier of malaria-causing protozoan is (i) female Anopheles mosquito (ii) cockroach (iii) housefly (iv) butterfly (d) The most common carrier of communicable diseases is (i) ant (ii) housefly (iii) dragonfly (iv) spider (e) The bread or idli dough rises because of (i) heat (ii) grinding (iii) growth of yeast cells (iv) kneading (f) The process of conversion of sugar into alcohol is called (i) nitrogen fixation (ii) moulding (iii) fermentation (iv) infection Soln: a) (ii) alcohol b) (ii) Streptomycin c) (i) female Anopheles mosquito d) (ii) housefly e) (iii) growth of yeast cells f) (iii) fermentation 3. Match the organisms in Column A with their action in Column B. AB(i) Bacteria(a) Fixing nitrogen(ii) Rhizobium(b) Setting of curd(iii) Lactobacillus(c) Baking of bread(iv) Yeast(d) Causing malaria(v) A protozoan(e) Causing cholera(vi) A virus(f) Causing AIDS(g) Producing antibodies Sol:- AB(i) Bacteria(e) Causing cholera(ii) Rhizobium(a) Fixing nitrogen(iii) Lactobacillus(b) Setting of curd(iv) Yeast(c) Baking of bread(v) A protozoan(d) Causing malaria(vi) A virus(f) Causing AIDS 4. Can microorganisms be seen with the naked eye? If not, how can they be seen? Soln: Microorganisms cannot be seen by the naked eye because they are very small. They can be seen by using a microscope. 5. What are the major groups of microorganisms? Soln: Major group of microorganisms are as follows Bacteria Fungi Protozoans Algae Viruses 6. Name the microorganisms which can fix atmospheric nitrogen in the soil. Soln: Rhizobium 7. Write 10 lines on the usefulness of microorganisms in our lives. Soln: Uses of microorganisms are listed below They are helpful in cleaning up of the environment. For example, the organic wastes (vegetable peels, remains of animals, faeces, etc.) are broken down into harmless and usable substances by bacteria. Curd contains several microorganisms. Of these, the bacterium, Lactobacillus promotes the formation of curd. It multiplies in milk and converts it into curd. Bacteria are also involved in the making of cheese, pickles and many other food items. Bacteria and yeast are also helpful for fermentation of rice idlis and dosa batter. Yeast reproduces rapidly and produces carbon dioxide during respiration. Bubbles of the gas fill the dough and increase its volume. This is the basis of the use of yeast in the baking industry for making breads, pastries and cakes. Microorganisms are used for the large scale production of alcohol, wine and acetic acid (vinegar). Antibiotics are being produced from bacteria and fungi. Microorganisms are helpful in producing vaccines against disease-causing agents. Some bacteria (Fig. 2.7) are able to fix nitrogen from the atmosphere to enrich the soil with nitrogen and increase its fertility. Microorganisms decompose dead organic waste of plants and animals to convert them into simple substances. These substances are again used by other plants and animals. Thus, microorganisms can be used to degrade the harmful and smelly substances and thereby clean up the environment. 8. Write a short paragraph on the harmful effects of microorganisms. Soln: Microorganisms cause diseases in plants and animals Ex; Cholera in humans is caused by bacteria called Vibrio cholera. In animals, the virus causes foot and mouth diseases. Microorganisms spoil the foods by decomposing the food material. Some microorganisms spoil leather and clothes. Microorganisms are responsible for food poisoning. 9. What are antibiotics? What precautions must be taken while taking antibiotics? Soln: Chemical agents that kill or stop the growth of disease-causing microorganisms are called antibiotics. Antibiotics should be taken only on the advice of a qualified doctor. Also, one must complete the course prescribed by the doctor.

    1Thank You

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