Most antibiotics target bacterial parasites interfering with various factors of growth or metabolism such as 1. synthesis of cell wall 2. bacterial protein synthesis 3. synthesis of nuclear membrane 4. mitochondrial function Select the correct answer using the code given below.

Antibiotics are antimicrobial drugs that selectively target bacterial growth and metabolism. A primary mechanism is the inhibition of bacterial cell wall synthesis, specifically targeting peptidoglycan biosynthesis, which makes the bacteria susceptible to osmotic lysis [2]. Another major target is bacterial protein synthesis, where drugs like tetracyclines and macrolides bind to the 30S or 50S ribosomal subunits to block translation [2]. Regarding the other options, bacteria are prokaryotic organisms that lack a well-defined nucleus and a nuclear membrane [1]; thus, antibiotics cannot target a non-existent nuclear membrane. Furthermore, while some antibiotics can affect metabolic pathways like ATP synthesis in specific bacteria, they do not target mitochondria, as mitochondria are organelles found in eukaryotic host cells, not in the bacteria themselves [2]. Therefore, only statements 1 and 2 are correct mechanisms for bacterial parasites.

Sources

1. [2] Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 3: Health: The Ultimate Treasure > 3.5.1 Treatment of diseases > p. 39
2. [1] Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 2: The Invisible Living World: Beyond Our Naked Eye > Snapshots > p. 24