The scientist who discovered the penicillin-producing mold was:
A. Louis Pasteur
B. Joseph Lister
C. Alexander Fleming
D. Robert Koch
Answer: Option C
Solution (By JKExamLibrary)
Alexander Fleming noticed in 1928 that a mold contaminant (Penicillium notatum) on a bacterial culture plate inhibited the growth of Staphylococcus aureus, leading to the discovery of penicillin, the first widely used antibiotic. Florey and Chain later purified it. Pasteur developed pasteurization.
Explanation:
Viruses are non-living outside a host cell and must hijack a host's cellular machinery to replicate, making them obligate intracellular parasites. They contain either DNA or RNA, not both (except some rare cases). They lack cell walls and metabolic machinery. Their status as living or non-living is debated, but they are biologically active only inside a host.
Explanation:
Viruses are non-living outside a host cell and cannot carry out metabolism or reproduce independently. They hijack the host cell's machinery to replicate. Hence they are obligate intracellular parasites. The reason correctly explains the assertion. Even though some debate exists on whether viruses are living, the statement that they are obligate parasites and lack metabolic machinery is accurate.
Consider the following statements about biodiversity:
1. Biodiversity includes genetic, species, and ecosystem diversity.
2. Hotspots are regions with high endemism and habitat loss.
3. The Western Ghats is a biodiversity hotspot.
Which of the above is/are correct?
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