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NEET Important Chapter- Microbes in Human Welfare

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Microbes in Human Welfare

Microbes in Human Welfare

This particular article contains the chapter named microbes in human welfare as per the  requirement of the students wishing to crack the NEET exam. It will be beneficial for the students who are looking for last minute revision.


This file contains all of the important concepts and also provides the insight of the exam pattern. By going thoroughly to this document the students can find out the answers to the important questions associated with the chapter such as what are microbes,what are the different kind of microbes that are helpful or beneficial for us, what is the role of microbes in household products, what are the microbes which can be used as biofertilizers etc.


Important Topics of Microbes in Human Welfare

  • Microbes in Household Products

  • Microbes in Industrial Products

  • Microbes in Sewage Treatment

  • Microbes in Production of Biogas

  • Microbes as Biocontrol Agents

  • Microbes as Biofertilisers


Important Concepts

Microbes

These are the minute unicellular organisms that are invisible to the naked eye. They are present everywhere such as in soil, water, air, inside our bodies etc. They are also known as microorganisms.


They are diverse and include viruses, bacteria, protozoa, fungi, viroids, prions etc. Although in the majority of cases they are pathogenic in nature and cause a variety of infections, they have an important role to play in human welfare.


Microbes in Household Products

Microorganism

Product

Lactobacillus

Curd

Saccharomyces cerevisiae

Bread


Propionibacterium shermanii

Penicillium roqueforti

Penicillium camemberti

Cheese

  • Swiss cheese

  • Roquefort cheese

  • Camembert cheese


Microbes in Industrial Products

1. Fermented Beverages

Saccharomyces cerevisiae which is commonly known as Brewer’s yeast has been used for a long period of time for the production of alcoholic beverages from the cereals and  fruit juices. Examples of fermented beverages include wine, beer, whisky, brandy or rum etc. 


2. Antibiotics 

Such types of medicines that are used to destroy bacteria. Penicillin was the first antibiotic that was produced from the fungus Penicillium notatum by Alexander Fleming. During world war II this antibiotic was extensively used to treat American soldiers.


The following table describes the different types of antibiotics and  the diseases against which they can be used.


Antibiotic name

Source

Diseases Against Used For

Bacitracin

Bacillus subtilis

Syphilis, Lymphedema or Reticulosis

Streptomycin

Streptomyces griseus

Meningitis, Pneumonia, Tuberculosis and local Infection

Chloromycetin

Streptomyces venezuelae

Typhoid

Erythromycin

Streptomyces erythreus

Typhoid, Whooping cough and diphtheria

Gentamicin

Micromonospora purpurea

Effective against Gram (+) bacteria

Tetracycline

Streptomyces aureofaciens

Acne, urinary and  intestinal tract infections, conjunctivitis


3. Vaccines

These are defined as an artificial way to activate the immune system to protect against infections. It was Edward Jenner who first developed the vaccine against smallpox. Now a variety of vaccines have been developed against various infections such as Polio, DPT, Measles, Covid-19 etc.


4. Enzymes and chemicals

Enzymes are biological catalysts. Nowadays, a variety of enzymes have been produced by using no. of microorganisms such as Streptococcus bacteria produces an enzyme called streptokinase, which is modified genetically and used as a clot-buster for removing clots from the blood vessels.


Different Kinds of Organic Acids and Their Sources

Organic Acid

Source

Citric acid

Aspergillus niger

Acetic acid

Acetobacter aceti

Lactic acid

Lactobacillus

Butyric acid

Clostridium butylicum

Ethanol

Saccharomyces cerevisiae


Bioactive molecules are those chemicals which are produced in small amounts in plants and  certain foods and  apart from the nutritional qualities they also produce varieties of physiological effects such as

1. Cyclosporin A is a suppressor of the immune system which is commonly used in organ 

    transplant patients and is produced by Trichoderma polysporum.

2. Statins that are commonly used to lower the blood cholesterol level are produced by 

    Monascus purpureus.


Microbes in Sewage Treatment

  • The municipal wastewater is called sewage. A major component of this wastewater is the human excreta, and  it also contains certain microbes that can be pathogenic. So, it can’t be discharged into the natural body such as rivers, lakes etc. without the treatment.

  • The sewage treatment is completed in two stages that are primary treatment and  secondary treatment.

  • Filtration of solid particles (known as suspended solids) and  sedimentation are done during the primary treatment.

  • Break-down of organic matter is done during the secondary treatment by using the biological microorganisms



Sewage Treatment Plant

Microbes in Production of Biogas

  • Biogas is the biofuel that is produced by the decomposition of organic matter.

  • It is a mixture of methane, hydrogen, and carbon dioxide.

  • The biogas plant is composed of a dome shaped structure where biogas is produced under anaerobic (in the absence of oxygen) conditions.   

  • Methanogens are the methane producing archaebacteria which belong to the Kingdom Monera. The example includes Methanobacterium.

  • They are mainly found in cattle dung and  in anaerobic sludge during sewage treatment. They grow in an anaerobic manner on cellulosic material and  produce a large amount of methane which is the main constituent of biogas, along with CO2 and H2


Biogas Plant

Microbes as Biocontrol Agents

Biocontrol is defined as the process which involves the use of biological methods for controlling plant diseases and pests.

Some examples of biocontrol agents are

  • Dragonflies and ladybugs 

  • Bacillus thuringiensis

  • Baculoviruses 

  • Trichoderma


Microbes Used as Biofertilizers

These are defined as biological products which contain living microorganisms. They enhance the nutrient quality of the soil. The microorganisms such as fungi, bacteria and  cyanobacteria are the main sources of biofertilizers. Example includes

  • Rhizobium 

  • Azotobacter and  Azospirillum

  • Mycorrhiza

  • Cyanobacteria such as Nostoc, Anabaena, Oscillatoria etc.


Solved Examples from the Chapter

1. Milk starts to coagulate when Lactic Acid Bacteria (LAB) is added to milk as a starter. Mention two benefits that LAB provides. 

Ans: The benefits that are provided by LAB are

1. It checks the growth of disease-causing microbes.

2. It converts milk into curd and  also increases the overall nutritional quality by increasing vitamin B12.

Key point to remember - Lactic acid bacteria converts the milk into the curd.


2. What is cyclosporin A? What is its importance?

Ans: Cyclosporin A  is an eleven-membered cyclic oligopeptide produced by Trichoderma Polysporum through fermentative activity.

Importance- It has antifungal, anti-inflammatory, and  immunosuppressive properties. It prevents the rejection reactions in organ transplantation by inhibiting the activation of T-cells.

Key point to remember - Cyclosporin A is produced by Trichoderma Polysporum.


3. What is sewage? In which way can this be harmful?

Ans: The municipal wastewater is called sewage. It contains human excreta and certain microbes. In general, it consists of 95.5% water and  0.1 to 0.5% organic and  inorganic matter. 

  • It can be harmful to us due to the presence of a variety of microorganisms in them, most of which are highly pathogenic.

  • The BOD (biochemical oxygen demand ) of sewage water is high which develops anaerobic conditions in water and  results in the death of aquatic fauna and  emits a foul smell due to incomplete oxidation of organic materials in the sewage.

Key point to remember - Sewage waste contains a large number of pathogenic bacteria and the biochemical oxygen demand is also high.


Solved Problems of Previous Year Question from the Chapter

1. High value of BOD indicates that ___

    A. Water is less polluted

    B. Water is pure

    C. Water is highly polluted

    D. Consumption of organic matter in water is higher

  Ans: The correct answer is “C”.

  BOD stands for biochemical oxygen demand, which is defined as the amount of oxygen  

  required by the microorganisms while performing the function of decomposition of 

  organic matter in the water. The greater the pollutant concentration, the greater will be   

  the value of BOD.


2. Secondary sewage treatment is mainly a ______

    A. Chemical process

    B. Biological process

    C. Physical process

    D. Mechanical process

    Ans: The correct answer is “B”.

    During secondary sewage treatment, the organic matter is mainly decomposed by the  

    microorganisms which grow in the form of flocs (which are defined as the bacteria 

    associated with fungal filaments and form the mesh like structures).


3. Thiobacillus is a group of bacteria helpful in carrying out

  1. Nitrogen fixation

  2. Chemoautotrophic fixation

  3. Nitrification

  4. Denitrification

      Ans: The correct answer is “D”.

Thiobacillus is a chemoautotrophic bacteria that denitrify the nitrate during the oxidation of compounds. The process of denitrification involves the conversion of oxides nitrogen to free nitrogen. 


Practice Questions

1. Give the full form of Bt. Name the insects killed by it.

Ans: Bt. stands for Bacillus thuringiensis. It kills a wide range of insects such as moths, beetles, mosquitoes, aphids, and termites.


2. Name the blank spaces a, b, c, and d from the table given below: 

Type of microbe

Scientific name

Product

Medical application

(i) Fungus

a

Cyclosporin A

b

(ii) c

Monascus purpureus

Statin

d


Ans:

Type of microbe

Scientific name

Product

Medical application

(i) Fungus

Trichoderma polypore

CyclosporinA

Acts as immunosuppressant

(ii) Yeast

Monascus purpureus

Statin

Acts as the blood cholesterol-lowering agent


3. Match the column I with column II

Microorganisms

Products

Lactobacillus

(iii) Citric acid

Saccharomyces cerevisiae

(ii) Curd

Aspergillus niger

(iv) Bread

Acetobacter aceti

(i) Acetic acid


Ans:

Microorganisms

Products

Lactobacillus

(ii) Curd

Saccharomyces cerevisiae

(iv) Bread

Aspergillus niger

(iii) Citric acid

Acetobacter aceti

(i) Acetic acid


Conclusion

This particular document contains all the necessary information that can be beneficial for the students who are preparing for the NEET exam and  can be really helpful for an effective and quick revision. It carries all the important concepts, questions from the past year NEET exam, mock test & also the Biology NCERT. One must make sure to try the Practice questions by themselves to test your knowledge and to get desired results.

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NEET Important Dates

NEET Important Dates

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NEET 2022 exam date and revised schedule have been announced by the NTA. NEET 2022 will now be conducted on 17-July-2022, and the exam registration closes on 20-May-2022. You can check the complete schedule on our site. Furthermore, you can check NEET 2022 dates for application, admit card, exam, answer key, result, counselling, etc along with other relevant information.
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NTA has announced the NEET 2022 application form release date on the official website https://neet.nta.nic.in/. NEET 2022 Application Form is available on the official website for online registration. Besides NEET 2022 application form release date, learn about the application process, steps to fill the form, how to submit, exam date sheet etc online. Check our website for more details.
NEET 2022 applicants should be aware of the eligibility criteria before applying to the exam. NTA has released all the relevant information on the official website, i.e. https://neet.nta.nic.in/. NEET 2022 aspirants should have passed Class 12th or any other equivalent qualifying examination in 2021, 2020, or students appearing in the Class 12th final exam in 2022 can also apply. For further details, visit our website.
As per the union government’s norms, NTA has released the NEET 2022 reservation criteria for different candidates’ categories (SC/ST/OBC/PwD), All India Quota, State Government Quota, Deemed Universities, and more. You can check more details on Vedantu website.
NEET 2022 Admit Card will be released by the NTA in the month of June 2022. Candidates can download the NEET admit card and hall ticket from the NEET official website i.e. https://neet.nta.nic.in/. For more details on the NEET admit card 2022, candidates can check Vedantu official website.
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"NEET 2022 free online mock test series for exam preparation are available on the Vedantu website for free download. Practising these mock test papers of Physics, Chemistry and Biology prepared by expert teachers at Vedantu will help you to boost your confidence to face the NEET 2022 examination without any worries. The NEET test series for Physics, Chemistry and Biology that is based on the latest syllabus of NEET and also the Previous Year Question Papers."
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NEET 2022 Cut Off

NEET 2022 Cut Off

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NTA is responsible for the release of the NEET 2022 cut off score. The qualifying percentile score might remain the same for different categories. According to the latest trends, the expected cut off mark for NEET 2022 is 50% for general category candidates, 45% for physically challenged candidates, and 40% for candidates from reserved categories. For the general category, NEET qualifying marks for 2021 ranged from 720-138 general category, while for OBC/SC/ST categories, they ranged from 137-108 for OBC, 137-108 for SC and 137-108 for ST category.
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NEET 2022 Results

NEET 2022 Results

The NEET 2022 result is published by NTA on https://neet.nta.nic.in/ in the form of a scorecard on 7-Sep-2022. The scorecard will include the roll number, application number, candidate's personal details, and the percentile, marks, and rank of the candidate. Only those candidates who achieve the NEET cut-off will be considered qualified for the exam.
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NEET 2022 state rank lists will be released by the state counselling committees for admissions to the 85% state quota and to all seats in private medical and dental colleges. NEET 2022 state rank lists are based on the marks obtained in entrance exams. Candidates can check the NEET 2022 state rank list on the official website or on our site.
The NTA will conduct NEET 2022 counselling at https://www.mcc.nic.in/. There will be two rounds of counselling for admission under All India Quota (AIQ), deemed and central universities, AIIMS, JIPMER, ESIC, and AFMC. A mop-up round of NEET counselling will be conducted excluding 15% AIQ seats, while the dates of NEET 2022 counselling for 85% state quota seats will be announced by the respective state authorities.
NTA is responsible for the release of the NEET 2022 cut off score. The qualifying percentile score might remain the same for different categories. According to the latest trends, the expected cut off mark for NEET 2022 is 50% for general category candidates, 45% for physically challenged candidates, and 40% for candidates from reserved categories. For the general category, NEET qualifying marks for 2021 ranged from 720-138 general category, while for OBC/SC/ST categories, they ranged from 137-108 for OBC, 137-108 for SC and 137-108 for ST category.
Want to know which Engineering colleges in India accept the NEET 2022 scores for admission to Engineering? Find the list of Engineering colleges accepting NEET scores in India, compiled by Vedantu. There are 1622 Colleges that are accepting NEET. Also find more details on Fees, Ranking, Admission, and Placement.
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FAQs on NEET Important Chapter- Microbes in Human Welfare

FAQ

1. Is the chapter ‘Microbes in Human Welfare’ important for NEET 2022?

Yes, it is important for the NEET exam because it covers most of the important topics and concepts that fetch high weightage in the exam.

2. Is NCERT enough for preparing for the NEET 2022 exam?

Yes, it is enough. One can score very well by going through it again and again because every time a person receives new information which is very important in terms of exams.

3. What are the important topics of the chapter ‘Microbes in Human Welfare’?

It is not a lengthy chapter and is important for NEET aspirants, hence the students should go through all the concepts in the chapter.