New answers tagged

0

In this case the authors appear to imply that the mechanism is primarily the accumulation of partially protective immunity resulting from earlier infection. From Table 1, we observed that 1) [p-bar] monotonically decreases as age increases; 2) [p-bar] decreases as q increases. [...] The first observation support the concept that some degree of ...


0

Until this study, medical dogma had been that when a bacterium develops resistance to a drug, it becomes weaker as a human pathogen. According to that very rosy scenario, drug-resistant strains should eventually extinguish themselves in the environment, because they can't compete with the original, drug-susceptible organism.


1

The "Description of the analyzed data set" section seems suspicious to me: In a nutshell, young women between the ages of 14 and 17 years old were identified and recruited by the project. ... At each follow-up visit during the study period, enrolled participants underwent STI testing and treatment. Also at each follow-up visit, the ...


2

I agree with @Maximilian that the phrase you quote is unclear, and we can't understand if it's talking about the number of cell walls of about the presence of cell walls: Most bacteria have at least 1 cell wall, meaning that some bacteria can have more than 1 This is wrong, as @Maximilian explained. But this: Most bacteria have a cell wall, meaning ...


1

The phrase you quote is a little unclear, but in looking at the page you link to I believe that @Ashafix was referring to Gram-positive (one cell membrane) and Gram-negative bacteria (two cell membranes). Each type has only one cell WALL, which refers to the structural peptidoglycan layer, which is between the two membranes in gram-negative bacteria, and ...


1

Peptidoglycan is formed by the linkage of molecules of NAM ( N-acetylmuramic acid) and NAG (N-acetylglucosamine) into a polysaccharide structure. Many of these structures are then formed into a lattice by crossbridges of polypeptides. In gram + bacterial cell walls many layers of this lattice are stacked up forming a rigid structure, that is external to ...


0

The bacterium always has a higher internal osmotic pressure (they contain a lot of stuff, and most of the time much more stuff than their surroundings). This pressure is contained by the membrane and cell wall, and when you destroy the cell wall the membrane alone is not strong enough, and the bacterium will spill its guts.



Top 50 recent answers are included