Que.11 What are the weeds? How can we control them?
Que.12 The most common carrier of communicable disease is
Que.13 Give one example of antibiotic.
Que.14 The process of conversion of sugar into alcohol is called
Que.15 Can microorganisms be seen with the naked eye?
Que.16 Name the microorganisms which can fix atmospheric nitrogen in the soil.
Que.17 What are antibiotics?
Que.18 What are the major groups of microorganisms? Write their name.
Que.19 Write 10 lines on the usefulness of microorganisms in our lives.
Que.20 Write a short paragraph on the harms caused by microorganisms.
Answers
Answer:
11) Tilling before sowing of crops helps in the uprooting and killing of weeds. Which may dry up and get mixed with soil. Weeds are also controlled by using certain chemicals, called weedicides. Weedicides are sprayed in the fields to kill the weeds.
12) housefly
13) amaxocillin
14) ethanol fermentation
15) no
16) rhizobium
17) An antibiotic is a type of antimicrobial substance active against bacteria.
18) Viruses, Bacteria, Archaea, Fungi, and Protists.
19) They are used in winemaking, baking, pickling and other food-making processes.
Alcoholic fermentation by yeast is widely used in the preparation of wine and bread.
A bacterium Lactobacillus promotes the formation of curd.
Microbes are used to reduce pollution.
They are used to increase soil fertility by fixing atmospheric nitrogen.
Microbes are also useful in preparing many medicines and antibiotics.
Certain microbes are also used in the biological treatment of sewage and industrial effluents.
Some microorganisms are taken as probiotics, that are believed to provide health benefits when consumed.
Bacteria are also involved in making cheese.
Acetobacter acetic is used for producing acetic acid from alcohol.
20) Microorganisms can prove very harmful to us, as they cause a number of diseases in human, plants and animals. Diseases in humans like common cold, tuberculosis, measles, chicken pox, polio, cholera, typhoid, hepatitis B, malaria, etc. are caused by microorganisms.