Home
Class 12
BIOLOGY
Alexander Fleming while working on ……….....

Alexander Fleming while working on ………..bacteria , observed Penicillium notatum growing in one of his unwashed culture plates around which these bacteria could not grow.

A

Streptococci

B

Diplococci

C

Staphylococci

D

Streptobacilli

Text Solution

AI Generated Solution

The correct Answer is:
**Step-by-Step Solution:** 1. **Identify the Scientist and Context**: The question refers to Alexander Fleming, a notable scientist known for his discovery of penicillin. 2. **Determine the Year of the Discovery**: Fleming made his discovery in the year 1928 while he was conducting experiments. 3. **Identify the Bacteria**: Fleming was working on Staphylococcus bacteria during his research. 4. **Describe the Observation**: While working with the Staphylococcus cultures, Fleming noticed that one of his unwashed culture plates had been contaminated with a fungus. 5. **Identify the Fungus**: The fungus that grew on the culture plate was identified as Penicillium notatum. 6. **Explain the Effect of the Fungus**: Fleming observed that around the Penicillium notatum, the colonies of Staphylococcus bacteria could not grow, indicating that the fungus produced a substance that inhibited bacterial growth. 7. **Conclusion**: This led to the discovery of penicillin, an antibiotic effective against many gram-positive bacteria, but not against gram-negative bacteria. **Final Answer**: Alexander Fleming was working on **Staphylococcus bacteria**. ---
Promotional Banner

Similar Questions

Explore conceptually related problems

Assertion : While working on staphylococci, Alexander Fleming observed that Penicillium notatum inhibits the growing of bacteria Reason : The inhibiting chemical was commercially extracted and its full potential was established by Alexander Fleming

Which of the following statements regarding antibiotics is not correct ? (i) Antibiotics are the attenuated microorganisms which in small concentration can kill or retard the growth of other harmful microorganisms. (ii) Penicillin was the first antibiotic discovered by Alexander Fleming (1928) while working on bacterium Staphylococcus aureus. (iii) The full potential of penicillin as an effective antibiotic was established by Ernest chain and Howard Florey. (iv) Fleming, Chain and Florey were awarded the Nobel Prize in 1945

What would happen if oxygen availability to activated sludge flocs is reduced? 1) It will slow down the rate of degradation of organic matter 2) The center of flocs will becomes anoxic, which would cause death of bacteria and eventually breakage of flocs 3) Flocs would increase in size as anerobic bacteria would grow around flocs 4) Protozoa would grow in large numbers

Assertion: Discovery of penicillin by Alexander Flemming was a serendipity. Reason: Flemming was working on Penicillium notatum along with Staphylococcus bacteria.

Which one of the following bacteria has found extensive use in genetic engineering work in plants?

The bacteria in a culture grows by 10% in the first hour, decreases by 10% in the second hour and again increases by 10% in the third hour. If the original count of the bacteria in a sample is 10000, find the bacteria count at the end of 3 hours.

A hospital technician, while doing some routine culturing of microorganisms in a lab, noticed a bacterial colony growing on a culture medium containing three different antibiotics. He identified the bacterium as one that did not cause a human disease, but he still reported his observation to the hospital administration. He was worried because

A farmer while growing grape plants in his garden, observes the following: (i) Fruit size normally remained small. (ii) Natural seed abortion. (iii) Reduced stem and leaf growth. Which problems could be solved by application of gibberellic acid during the development of fruits?