Antibiotics and Immunity

This is the correct answer.

Correct matching is A - 4, B - 2, C - 1, D - 3.

'Antibiotics' is the correct word.

Streptomycin is the first antibiotic drug of a class of drugs called aminoglycosides and it was the first antibiotic remedy for tuberculosis.

Potato Dextrose Agar (PDA) is a standard culture medium used to grow fungi and some bacteria in Petri dishes. It provides nutrients from potato infusion and dextrose (sugar). Glucose alone lacks other nutrients, while bone marrow and blood serum are not standard solid media for Petri dish cultures.

Lactobacilli have both aciduric and acidogenic potential, so they are crucial for progression of caries.

E. faecalis is the most commonly found organism in failed root canal cases. It is rarely found in infected but untreated root canal cases.

Ursolic acid inhibits the growth of human epidermoid carcinoma cells by affecting tyrosine kinase activity.

The capsule of Bacillus anthracis is entirely made up of D-glutamic acid. This amino acid is rare as most of the other capsules contain L form of amino acid.

This option is correct because chocolate blood agar is a non-selective, enriched growth medium used for isolation of pathogenic bacteria.

Enterococcus and Streptococcus are examples of catalase-negative bacteria.

This option is correct.

Penicillium notatum is the original fungus from which Alexander Fleming isolated penicillin in 1928, revolutionizing medicine. Other Penicillium species may produce different compounds, but notatum is famous for the first antibiotic discovery.

Alcaligenes faecalis, Enterobacter aerogenes, Klebsiella pneumoniae: All are Gram-negative bacteria.

Catalase Test: The catalase test is done by placing a drop of hydrogen peroxide on a microscope slide. If the bacteria possess catalase, when a small amount of bacterial isolate is added to hydrogen peroxide, bubbles of oxygen are observed. If the mixture produces bubbles or froth, the organism is said to be 'catalase-positive' otherwise it is 'catalase-negative’. Enterobacter, Klebsiella, Nocardia, and Staphylococcus: All are catalase-positive bacteria.