Which of the following statements is incorrect?a)Pathogenic bacteria c...
Antibiotics are substances produced by micro organisms which in low concentration are antagonistic then the growth of other micro-organisms (Waksman, 1942 medicinally antibiotics are those organic secretions which destroy or check the growth of different pathogens without hanning the host. Maximum number of antibotics are produced by mucelial bactera known as Actinomucetes. E.g., Streptomucin-Streplomyces groseus, Chloromycetin or chloramphenicol-Streptomyces venezuelae and S.Lavendulae.
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Which of the following statements is incorrect?a)Pathogenic bacteria c...
Incorrect Statement: A large number of antibiotics are produced by Actinomycetes (e.g. Streptomyces), which are a class of Fungi.
Explanation:
• Actinomycetes are not fungi, they are a group of Gram-positive bacteria that form branching filaments, and they are an important source of antibiotics.
• Antibiotics are natural substances produced by microorganisms, including bacteria, fungi, and actinomycetes, to inhibit the growth of other microorganisms.
• Streptomyces is the most well-known genus of Actinomycetes, and it has been a prolific source of antibiotics, including streptomycin, tetracycline, erythromycin, and vancomycin.
• Fungi, on the other hand, also produce antibiotics, such as penicillin and cephalosporin, but they are not a major source of antibiotics compared to Actinomycetes.
Therefore, option B is incorrect, and the correct statement is that Actinomycetes are a class of bacteria that produce a large number of antibiotics.
Which of the following statements is incorrect?a)Pathogenic bacteria c...
Incorrect Statement:
b) A large number of antibiotics are produced be Actinomycetes (eg. Streptomyces), which are a class of Fungi.
Explanation:
Actinomycetes are not fungi, they are a group of Gram-positive bacteria that form branching filaments, similar to fungi. They are commonly found in soil and are responsible for the production of a large number of antibiotics. Some examples of antibiotics produced by Actinomycetes include streptomycin, tetracycline, and erythromycin.
Correct Statements:
a) Pathogenic bacteria cause 90% of human diseases.
This statement is correct. Pathogenic bacteria are responsible for causing a variety of human diseases such as tuberculosis, cholera, and pneumonia.
c) N2-fixing bacteria pick up free N2 from soil atmosphere and convert it into nitrogenous compounds.
This statement is also correct. N2-fixing bacteria are important for the nitrogen cycle as they convert atmospheric nitrogen into a form that can be utilized by plants and other organisms. This process is called nitrogen fixation and is essential for the growth and development of many living organisms.
d) Archaebacteria differ from other bacteria in having a different cell wall structure and this feature is responsible for their survival in extreme conditions.
This statement is correct. Archaebacteria are a group of microorganisms that are distinct from other bacteria due to their unique cell wall structure. This feature allows them to survive in extreme conditions such as high temperatures, high salinity, and acidic environments. Some examples of extremophilic archaebacteria include thermophiles, halophiles, and acidophiles.
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