Find the best tutors and institutes for Class 12 Tuition
Q5:
In which way have microbes played a major role in controlling diseases caused by harmful bacteria?
Solution :
Step 1: Identification of Therapeutic Agents
Microbes, primarily fungi and certain bacteria, serve as the primary source for the production of antibiotics. Antibiotics are chemical substances produced by microorganisms which, in low concentrations, can kill or retard the growth of other disease-causing microorganisms [Per Waksman’s definition of antibiotics].
Step 2: Mechanism of Action Against Pathogenic Bacteria
The microbial products function through various biochemical pathways to inhibit bacterial proliferation:
- Inhibition of Cell Wall Synthesis: Antibiotics like Penicillin interfere with the synthesis of peptidoglycan, leading to osmotic lysis of the bacterial cell.
- Protein Synthesis Inhibition: Agents like Streptomycin and Tetracycline bind to the $70S$ bacterial ribosomes, preventing the translation of bacterial mRNA into functional proteins.
- Nucleic Acid Synthesis Interference: Certain antibiotics inhibit DNA gyrase or RNA polymerase, halting bacterial replication.
Step 3: Key Examples and Sources
| Antibiotic | Microbial Source | Target Pathogen Type |
|---|---|---|
| Penicillin | Penicillium notatum (Fungus) | Gram-positive bacteria |
| Streptomycin | Streptomyces griseus (Actinobacteria) | Gram-negative bacteria (e.g., Mycobacterium tuberculosis) |
| Bacitracin | Bacillus subtilis (Bacteria) | Various bacterial strains |
Step 4: Role in Modern Medicine
Microbes have transformed the treatment of once-fatal bacterial infections. By identifying these antimicrobial compounds, medical science can now manage diseases such as:
- Plague: Controlled via Streptomycin.
- Whooping Cough (Kali Khansi): Managed through targeted antibiotic intervention.
- Diphtheria (Gal ghotu): Effectively treated using microbial-derived antitoxins and antibiotics.
Step 5: Visual Representation of Antibiotic Inhibition
Final Solution: Microbes play a major role in controlling bacterial diseases primarily through the production of antibiotics—secondary metabolites that possess the biochemical capacity to specifically target and disrupt essential bacterial life processes such as cell wall biosynthesis, protein synthesis, and DNA replication, thereby eradicating or inhibiting the pathogens responsible for severe human ailments.
More Questions from Class 12 Biology Microbes in Human Welfare EXERCISES
- Q1: Bacteria cannot be seen with the naked eyes, but these can be seen with the help of a microscope. If you have to carry a sample from your home to your biology laboratory to demonstrate the presence of microbes with the help of a microscope, which sample would you carry and why?
- Q1: Bacteria cannot be seen with the naked eyes, but these can be seen with the help of a microscope. If you have to carry a sample from your home to your biology laboratory to demonstrate the presence of microbes with the help of a microscope, which sample would you carry and why?
- Q2: Give examples to prove that microbes release gases during metabolism.
- Q2: Give examples to prove that microbes release gases during metabolism.
- Q3: In which food would you find lactic acid bacteria? Mention some of their useful applications.
- Q3: In which food would you find lactic acid bacteria? Mention some of their useful applications.
- Q4: Name some traditional Indian foods made of wheat, rice and Bengal gram (or their products) which involve use of microbes.
- Q4: Name some traditional Indian foods made of wheat, rice and Bengal gram (or their products) which involve use of microbes.
- Q5: In which way have microbes played a major role in controlling diseases caused by harmful bacteria?
- Q6: Name any two species of fungus, which are used in the production of the antibiotics.
- Q6: Name any two species of fungus, which are used in the production of the antibiotics.
- Q7: What is sewage? In which way can sewage be harmful to us?
- Q7: What is sewage? In which way can sewage be harmful to us?
- Q8: What is the key difference between primary and secondary sewage treatment?
- Q8: What is the key difference between primary and secondary sewage treatment?
- Q9: Do you think microbes can also be used as source of energy? If yes, how?
- Q9: Do you think microbes can also be used as source of energy? If yes, how?
- Q10: Microbes can be used to decrease the use of chemical fertilisers and pesticides. Explain how this can be accomplished.
- Q10: Microbes can be used to decrease the use of chemical fertilisers and pesticides. Explain how this can be accomplished.
- Q11: Three water samples namely river water, untreated sewage water and secondary effluent discharged from a sewage treatment plant were subjected to BOD test. The samples were labelled \(A\), \(B\) and \(C\); but the laboratory attendant did not note which was which. The BOD values of the three samples \(A\), \(B\) and \(C\) were recorded as 20mg/L, 8mg/L and 400mg/L, respectively. Which sample of the water is most polluted? Can you assign the correct label to each assuming the river water is relatively clean?
- Q11: Three water samples namely river water, untreated sewage water and secondary effluent discharged from a sewage treatment plant were subjected to BOD test. The samples were labelled (A), (B) and (C); but the laboratory attendant did not note which was which. The BOD values of the three samples (A), (B) and (C) were recorded as (20mg/L), (8mg/L) and (400mg/L), respectively. Which sample of the water is most polluted? Can you assign the correct label to each assuming the river water is relatively clean?
- Q12: Find out the name of the microbes from which Cyclosporin \(A\) (an immunosuppressive drug) and Statins (blood cholesterol lowering agents) are obtained.
- Q12: Find out the name of the microbes from which Cyclosporin (A) (an immunosuppressive drug) and Statins (blood cholesterol lowering agents) are obtained.
- Q13(a): Find out the role of microbes in the following and discuss it with your teacher. (a) Single cell protein (SCP)
- Q13(a): Find out the role of microbes in the following and discuss it with your teacher. (a) Single cell protein (SCP)
- Q13(b): Find out the role of microbes in the following and discuss it with your teacher. (b) Soil
- Q13(b): Find out the role of microbes in the following and discuss it with your teacher. (b) Soil
- Q14: Arrange the following in the decreasing order (most important first) of their importance, for the welfare of human society. Give reasons for your answer. Biogas, Citric acid, Penicillin and Curd
- Q14: Arrange the following in the decreasing order (most important first) of their importance, for the welfare of human society. Give reasons for your answer. Biogas, Citric acid, Penicillin and Curd
- Q15: How do biofertilisers enrich the fertility of the soil?
- Q15: How do biofertilisers enrich the fertility of the soil?
CBSE Solutions for Class 12 Biology Microbes in Human Welfare
Chapters in CBSE - Class 12 Biology
- Reproduction in Organisms
- Human Reproduction
- Reproductive Health
- Principles of Inheritance and Variation
- Molecular Basis of Inheritance
- Evolution
- Human Health and Disease
- Strategies for Enhancement in Food Production
- Biotechnology: Principles and Processes
- Biotechnology and Its Applications
- Organisms and Populations
- Ecosystem
- Biodiversity and Conservation
- Environmental Issues
Top Tutors who teach Microbes in Human Welfare
Top Tutor
Siraspur, Delhi
9 yrs of
Exp
21 students
1554 hrs of classes completed
500
per hour
Online Classes
Tutor's home
I am well aware how to use keywords to solve questions in mcq's and case study. I have good knowledge and presentation of my subject. Students can take mock test and get pdf for exam sample paper.
Seema Ma’am has been teaching me Accounts since Grade 11, and now I’m continuing Grade 12 with her as well. Her explanation style is absolutely flawless and extremely easy to understand. She teaches every concept from the basic level, which makes even difficult topics feel simple and clear. She tells keywords and also gives tricks and hacks which will tackle the twists mcqs and questions...also she made me practice a lot through worksheets and sample papers which helped me to complete my paper on time. I am very confident with my accounts subject because of her guidance and teaching-style.
Top Tutor
Karampura, Delhi
10 yrs of
Exp
1 student
2500
per hour
Online Classes
Student's Home
I teach and help students to achieve immediate and long term goals. My experience as a personal tutor and the founder of an online educational startup 'MinDely' has helped him gain knowledge of child psychology and understanding students needs and takes measures accordingly. I plan the lessons as per the students ability to cope up and moreover upon their needs. My teaching technique is student friendly and easy to understand which helps students understand it better. Weekly test conducted by him helps the parents to know the students performance.
Top Tutor
Bhamian Khurd, Ludhiana
20 yrs of
Exp
2 students
12076 hrs of classes completed
300
per hour
Online Classes
Tutor's home
I am the author of seven books and a proud recipient of the Best Teacher Award from a reputed CBSE school. With over eight years of teaching experience at the school level and fifteen years of expertise in teaching Communication Skills and English Literature at a prestigious university, I bring a strong academic foundation and practical understanding of student development. My diverse teaching background has enabled me to mentor learners with varying abilities, helping them grow intellectually, linguistically, and personally. With this rich experience, I strive to ensure the all-around development of every student, fostering confidence, clarity of thought, and a lasting appreciation for the English language.
Top Tutor
Tollygunge, Kolkata
5 yrs of
Exp
3 students
38 hrs of classes completed
800
per hour
Online Classes
I have been giving tuitions to Class 12 students since October 2015. I was then in 2nd year of BSc Physics from the renowned 200 years old university, Presidency University. In total I taught 2 Class 12 students in Kolkata and 9 Class 12 students in Delhi. Currently I am teaching a Class 11 student from JNU Quarters Maths, Physics and Chemistry via Zoom app. I have whiteboard, colourful pens and other requirements to ease the teaching in a great way.
Top Tutor
New Bowenpally, Hyderabad
20 yrs of
Exp
27 students
437 hrs of classes completed
800
per hour
Online Classes
Tutor's home
every year 100s of my students pass out in chemistry more the 95% in CBSE, ISE and other state board exams
Vinod Sir is an exceptional faculty for IIT coaching. He explains complex concepts like Thermodynamics in a very simple, clear, and easy-to-understand manner. His teaching style makes even difficult topics interesting and accessible to every student. His strong conceptual approach and ability to simplify challenging problems are truly commendable. I highly recommend Vinod Sir to anyone preparing for IIT/JEE.
