Antibiotics and Immunity

The ability to ingest bacteria and killing them is a major feature of these professional phagocytic cells. Loss of neutrophils renders the host very susceptible to overwhelming infection.

Alexander Fleming discovered penicillin in 1928, and it is widely recognized as the first true antibiotic used in medicine.

Antibiotics are designed to either inhibit the growth of bacteria (bacteriostatic) or kill the bacteria directly (bactericidal).

Antibiotics are effective against bacteria but do not work against viruses, as viruses lack the cellular machinery that antibiotics target.

Antibiotics are substances that inhibit the growth of or destroy microorganisms, specifically bacteria and fungi. They are ineffective against viruses, which require antivirals.

Antiseptics can be used to kill microorganisms  or prevent their multiplication. Antiseptics do not harm the living tissues. Therefore, they can be applied on cuts and wounds. Dettol, cetavelon, savlon, acriflavin, gentian-violet, mercuro chrome, boric acid and potassium permanganate are some examples.

It is an antiseptic. An antiseptic is used to kill bacteria or prevent their multiplication. Antiseptics do not harm the living tissues. Therefore, they can be applied on cuts and wounds.

Antibiotics are chemical substances produced by microorganisms or synthesized to inhibit the growth of or kill bacteria.

Antibiotics work by targeting specific cellular processes in bacteria, such as cell wall synthesis or protein production, which are referred to as biochemical pathways.

Antibiotics are designed to target bacterial structures or pathways. Viruses have different structures and replicate differently, so antibiotics are ineffective against them.

Antibiotics are antimicrobial substances that act against bacteria. They can target various types of bacteria and other microbes, making both 1 and 2 the correct scope.

Bordeaux mixture is a combination of copper sulfate and lime, used as an inorganic fungicide to control fungal diseases in plants.

Tetracycline is a broad-spectrum antibiotic discovered in 1948, used to treat various bacterial infections. While it can be used to treat plague (caused by Yersinia pestis), it is not exclusively an 'anti-plague drug' - it's used for many conditions including pneumonia, acne, urinary tract infections, and more. Among the given options, only A is in the correct category (drug/medicine), though the description is imprecise. The other options are completely incorrect.

Gram-positive bacteria take up the crystal violet stain used in the test, and then appear to be purple-coloured when seen through a microscope.

Viruses are intracellular parasites that use the host's cellular machinery to replicate, making it very difficult to design drugs that target the virus without harming the host cells. Bacteria, fungi, and protozoa have distinct metabolic pathways that are easier to target.