What is a consequence of blocking folic acid synthesis in bacteria?

Blocking folic acid synthesis in bacteria has a direct impact on the production of nucleotides, which are essential building blocks for DNA and RNA. Folic acid, or vitamin B9, is a critical component in the synthesis of nucleic acids because it is involved in the creation of purines and pyrimidines. Without adequate folic acid, bacteria cannot effectively replicate their DNA or synthesize RNA, leading to interruptions in cell division and growth. This consequence is particularly significant in rapidly dividing bacterial populations, where the demand for DNA and RNA is high.

The other options, while potentially relevant to bacterial physiology, do not directly relate to the consequences of inhibiting folic acid synthesis. For example, increased oxidative stress typically results from exposure to reactive oxygen species rather than from folic acid interference. Cellular swelling might occur due to osmotic imbalances or cell wall integrity issues, while alterations in membrane fluidity pertain to the properties of lipids and phospholipids in the cell membrane, which are not directly affected by folic acid synthesis. Therefore, the interruption of DNA and RNA synthesis is the most accurate consequence of blocking folic acid synthesis in bacteria.