NCERT Solutions for Class 8 Science Chapter 2 - Microorganisms Friend and Foe

NCERT Solutions for Class 8 Science Chapter 2 Microorganisms Friend and Foe

Edited By Irshad Anwar | Updated on Oct 03, 2024 11:26 AM IST

NCERT Solutions for Class 8 Science Chapter 2 Microorganisms Friend and Foe: Have you ever wondered why stale bread kept in a dark and humid area grows white coloured mesh over it? With Microorganisms friend and foe Class 8 Solutions: you will learn How does the milk with a little curd kept by your mother in a hotter place turn into curd the next morning? All these questions have been discussed in solutions to NCERT Class 8 Science Chapter 2 - Microorganisms Friend and Foe, it is due to the presence of microorganisms. Class 8 Science Chapter 2 deals with the role of microorganisms in our lives. Learning would be easier, and you will learn all the concepts while going through the Class 8 Science Chapter 2 question answer. NCERT Solutions for Class 8 Science provide detailed solutions to each chapter of Class 8 Science. Scroll down to go through the questions and answers given in NCERT Solutions for Class 8 Science Chapter 2.

NCERT Solutions for Class 8 Science Microorganisms Friend and Foe

To effectively prepare for their exams, students must regularly practice these solutions. Students can fully comprehend the topic with the help of these solutions. If they want to take biology in higher secondary schools, they should read the chapter Microorganisms Friend and Foe. Students in the 8th standard should carefully review the NCERT Solutions for Class 8 Science Chapter 2. These responses will assist them in mastering the ideas covered in the chapter Microorganisms: Friend and Foe, which are listed above. Subject matter experts developed the NCERT Solutions for Class 8 in accordance with the most recent CBSE syllabus

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NCERT Solutions for Class 8 Science Chapter 2 - Microorganisms: Friend and Foe

Class 8 Science Chapter 2 NCERT Solutions:

What are Microorganisms?

Microorganisms are the smallest organisms that cannot be seen with the naked eye. Now, you must be wondering: if they cannot be seen with the naked eye, then how did we first get to know about them? It was mainly due to the invention of an instrument called the microscope. You will learn about the structure and workings of a microscope in Class 8 Science Chapter 2 - Microorganisms Friend and Foe. you will learn many such concepts in Microorganisms Friend and foe Class 8 NCERT Solutions. These solutions are part of NCERT Solutions for Class 8.

Types of Microorganisms:

There are five groups of microorganisms around us. These include

Bacteria,
Fungi,
Protozoa
Algae
Viruses.

Microorganisms friend and foe Class 8 Solutions explains that Among the above-given microorganisms, viruses are different from the rest. How? You will learn all about in Chapter 2 Science Class 8 - Microorganisms Friend and foe of NCERT. You can also check out the NCERT Solutions (classes 6 to 12) for other chapters in science or even for other subjects by using the given links on this page.

Microorganisms: Friend and Foe Class 8 Science NCERT Textbook Questions Answers

Class 8 Science Chapter 2 question answer are given below:

Class 8 Microorganisms Friend and Foe NCERT Solutions:

Q.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 __________.

Answer:

(a) Microorganisms can be seen with the help of a Microscope .
(b) Blue green algae fix Nitrogen directly from air and enhance fertility of soil.
(c) Alcohol is produced with the help of Yeast .
(d) Cholera is caused by Bacteria .

Microorganisms Friend and Foe Class 8 Solutions

Q.2.(a) Tick the correct answer. Yeast is used in the production of (i) sugar

(ii) alcohol

(iii) hydrochloric acid

(iv) oxygen

Answer:

(a) Yeast is used in the production of (ii) Alcohol

Microorganisms Friend and Foe Class 8 NCERT Solutions:

Q.2(b). Tick the correct answer

The following is an antibiotic

(i) Sodium bicarbonate

(ii) Streptomycin

(iii) Alcohol

(iv) Yeast

Answer:

(b) The following is an antibiotic (ii) Streptomycin

Class 8 Science Chapter 2 Question Answer:

Q.2(c). Tick the correct answer

Carrier of malaria-causing protozoan is

(i) female Anopheles mosquito (ii) cockroach

(iii) housefly (iv) butterfly

Answer:

Class 8 Science Chapter 2 NCERT Solutions:

Q.2(d). The most common carrier of communicable diseases is

(i) ant (ii) housefly (iii) dragonfly (iv) spider

Answer:

(d) The most common carrier of communicable diseases is (ii) housefly.

Class 8 Microorganisms Friend and Foe NCERT Solutions:

Q.2(e). Tick the correct answer

The bread or idli dough rises because of

(i) heat (ii) grinding (iii) growth of yeast cells (iv) kneading

Answer:

(e) The bread or idli dough rises because of (iii) The growth of yeast cells.

Microorganisms Friend and Foe Class 8 Questions and Answers:

Q.2(f). Tick the correct answer

The process of conversion of sugar into alcohol is called

(i) nitrogen fixation (ii) moulding (iii) fermentation (iv) infection

Answer:

(f) The process of conversion of sugar into alcohol is called (iii) Fermentation

NCERT Solutions for Class 8 Science Chapter 2 - Microorganisms Friend and Foe

Q. 3. Match the organisms in Column A with their action in Column B

A B
(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

Answer:

Column A	Column B
Bacteria	Causing Cholera
Rhizobium	Fixing nitrogen
Lactobacillus	Setting of curd
Yeast	Baking of bread
A protozoan	Causing malaria
A virus	Causing AIDS

Class 8 Microorganisms Friend and Foe NCERT Solutions

Q. 4. Can microorganisms be seen with the naked eye? If not, how can they be seen?

Answer:

No, the microorganisms cannot be seen with the human naked eye because they are too small to be seen. microorganisms can be seen with the help of a scientific instrument called microscope.

Example- fungus on bread.

Microorganisms Friend and Foe Class 8 Solutions:

Q. 5. What are the major groups of microorganisms?

Answer:

The major groups of microorganisms are as follows-

(i) Bacteria- unicellular organisms. most common examples of bacteria are Salmonella typhi, Rhizobium, Mycobacterium etc. Typhoid and tuberculosis (TB) are bacterial diseases.

(ii) Fungi- Multicellular organisms which feed on dead and deaying matter. Bread mould is common examples.

(iii) Protozoa- Unicellular organisms wihich are mostly parasitic. Organisms like Amoeba, Plasmodium etc are under this category. Dysentery and malaria are caused by protozoans.

(iv) Virus- Acellular organisms which reproduce only inside the cells of the host organism. These cause diseases like chicken pox and polio.

(v) Algae- They are unicellular or multicellular organism. Spirogyra, Chlamydomonas, Ulva are some of the examples of algae.

Q6. Name the microorganisms which can fix atmospheric nitrogen in the soil.

Answer:

The microorganism that can fix atmospheric nitrogen in the soil are bacteria such as Rhizobium , and blue-green algae. These converted nitrogenous compounds can be easily used by plants for the plant protein synthesis and other purposes.

Q 7. Write 10 lines on the usefulness of microorganisms in our lives.

Answer :

Microorganisms are useful for us in the following ways-

Microorganisms are used to increase the fertility of the soil by fixing the atmospheric nitrogen with the help of blue-green algae and Rhizobium.
Antibiotics which are obtained from microorganisms are used to control the diseases.
There are some bacteria which can turn nitrogen compounds found in the soil into nitrogen gas which is further released into the environment.
Bacterium Lactobacillus reproduces in milk and promotes the formation of curd.
Microorganisms especially yeast can be used for the industrial production of alcohol, wine and acetic acid (vinegar).
Microbes are used to reduce pollution. example- bacteria and fungi break down the dead bodies and excreta to form inorganic compounds which are absorbed by plants
Yeast reproduces rapidly and produces carbon dioxide during respiration. Bubbles of the gas fill the dough and increase its volume. Thus they have a use in making of bread.

Microorganisms Friend and Foe Class 8 NCERT Solutions

Q. 8. Write a short paragraph on the harmful effects of microorganisms.

Answer:

The harmful effects of microorganisms are given below-

Microorganisms cause diseases in humans as well as animals. For example cholera and TB are caused by bacteria in humans.
In plants also diseases are caused by microorganisms. For example, citrus canker in plants is caused by bacteria and rust of wheat is caused by fungi.
Food poisoning is also caused by the microorganisms that spoils our food by producing some toxic substances. For example- when the bread is left in under moist condition gets spoilt by fungus.

Class 8 Science Chapter 2 Question Answer

Q. 9. What are antibiotics? What precautions must be taken while taking antibiotics?

Answer:

Antibiotics- These are medicines that kill or stop the growth of the disease-causing microorganisms. There are a lot of antibiotics which are produced with the help of bacteria and fungi. Streptomycin, tetracycline and erythromycin are some of the commonly known antibiotics which are made from fungi and bacteria.

Precautions that must be taken while using antibiotics-

Antibiotics must be taken obly on the prescrition of a doctor.
must finish the course prescribed by the doctor.
An antibiotic should be taken in the right amount only. Antibiotics taken unnecessarily may kill beneficial bacteria in the body.

Class 8 Science Chapter 2 NCERT Solutions

Q. 10. What precautions must be taken while taking antibiotics?

Answer:

Those medicines kill or stop the growth of the disease-causing microorganisms are called antibiotics. Antibiotics are
being produced from bacteria and fungi.

Precaution to be taken while using antibiotics-

antibiotics should be taken only on the advice of a qualified doctor.
must finish the course prescribed by the doctor.
An antibiotic should be taken in the right amount. antibiotics taken unnecessarily may kill beneficial bacteria in the body.

NCERT Solutions for Class 8 Science Chapter 2 Microorganisms Friend and Foe

Important topics in Class 8 Science Chapter 2 Microorganisms Friend and Foe:

Section Name	Topic Name
2	Microorganisms Friend and Foe
2.1	Microorganisms
2.2	Where do Microorganisms Live?
2.3	Microorganisms and Us
2.4	Harmful Microorganisms
2.5	Food Preservation
2.6	Nitrogen Fixation
2.7	Nitrogen cycle

Highlights of NCERT Solutions for Class 8 Science Chapter 2:

The key features of Class 8 Microorganisms Friend and Foe NCERT Solutions:

Now that you know the Microorganisms Friend and Foe Solutions and have understood the topics well, it's time to practice the Class 8 Science Chapter 2 question answer.
Check previous year's questions from the exam and practice Microorganisms Friend and Foe Class 8 Questions and Answers
to know your preparation levels.
NCERT Solutions for Class 8 is the base of your learning for further classes.
Class 8 Science Chapter 2 NCERT Solutions will also boost your knowledge.
NCERT solutions for Class 8 Science Chapter 2 Microorganisms: Friend and Foe will also help you to understand all the concepts easily.
Class 8 Science Ch 2 question answer are created by experienced subject matter experts.
NCERT Solutions for Class 8th Science aims to ease the learning and make it more interesting to build foundation strong.
Class 8 chapter 2 science is important to clear all basic concepts related to microoganisms.
The Science Chapter 2 Class 8 Solutions are developed by thE experienced subject experts and are totally reliable.
Class 8 Science Chapter 2 PDF are easy to download and use offline.

NCERT Solutions For Class 8th Science: Chapter-wise

Chapter 1	Crop Production and Management
Chapter 2	Microorganisms Friend and Foe In Microorganisms
Chapter 3	Synthetic Fibres and Plastics
Chapter 4	Materials Metals and Non Metals
Chapter 5	Coal and Petroleum
Chapter 6	Combustion and Flame
Chapter 7	Conservation of Plants and Animals
Chapter 8	Cell Structure and Functions
Chapter 9	Reproduction in Animals
Chapter 10	Reaching the Age of Adolescence
Chapter 11	Force and Pressure
Chapter 12	Friction
Chapter 13	Sound
Chapter 14	Chemical Effects of Electric Current
Chapter 15	Some Natural Phenomena
Chapter 16	Light
Chapter 17	Stars and the Solar System
Chapter 18	Pollution of Air and Water

NCERT Solutions For Class 8th: Subject-wise

NCERT Solutions for Class 8 Maths

NCERT Solutions for Class 8 Science

Also, Check NCERT Books and NCERT Syllabus here

NCERT Books Class 8 Science

NCERT Syllabus Class 8 Science

NCERT Books Class 8

NCERT Syllabus Class 8

We hope you will ace your examination with the help of NCERT Solutions for Class 8 Science Chapter 2 Microorganisms Friends and Foe.

Frequently Asked Questions (FAQs)

1. Whether the chapter Microorganisms Friends and Foe is useful for higher studies

Yes, the concepts studied in the chapter are useful for higher studies. The class 12 NCERT topic biology and human welfare is a continuation of this chapter. This chapter can be a foundation for the NEET exam.

Also Read

NCERT Solutions for Class 8 Science Chapter 11 Force and Pressure

NCERT Solutions for Class 8 Science Chapter 10 Reaching The age of adolescence

NCERT Solutions for Class 8 Science Chapter 9 Reproduction in Animals

NCERT Solutions for Class 8 Science Chapter 7 Conservation of Plants and Animals

NCERT Solutions for Class 8 Science Chapter 3 Synthetic Fibres and Plastics

NCERT Solutions for Class 8 Science Chapter 2 Microorganisms Friend and Foe

NCERT Books for Class 8 English 2024 - Download PDF

NCERT Syllabus for Class 8 2024-25 - Download All Subjects PDF

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