What is an explanation of how antibiotic resistance occurs?

Answer 1

Bacterial resistances are developed due to mutations that are passed down from generations of bacteria. Antibiotics generally kill all but the strongest bacteria or bacteria that have resistances to these antibiotics, resulting in only these bacteria reproducing, passing on the antibiotic resistances to future generations. Over time, entire populations of bacteria can develop a resistance to an antibiotic if they are frequently exposed to it. Bacterial resistances are developed due to mutations that are passed down from generations of bacteria. Antibiotics generally kill all but the strongest bacteria or bacteria that have resistances to these antibiotics, resulting in only these bacteria reproducing, passing on the antibiotic resistances to future generations. Over time, entire populations of bacteria can develop a resistance to an antibiotic if they are frequently exposed to it. Bacterial resistances are developed due to mutations that are passed down from generations of bacteria. Antibiotics generally kill all but the strongest bacteria or bacteria that have resistances to these antibiotics, resulting in only these bacteria reproducing, passing on the antibiotic resistances to future generations. Over time, entire populations of bacteria can develop a resistance to an antibiotic if they are frequently exposed to it.

Answer 2

Resistance can arise from random mutations in the bacteria's genome that provides for resistance to the antibiotic.

It can also (and this is usually how it happens) be passed down to offspring. For example, a colony of bacteria are exposed to some antibiotic that kills all but a few. Those few contain something in their genome that has allowed them to survive. They reproduce and now the offspring are resistant to the antibiotic. So the colony will rebuild, now resistant to the antibiotic.

Answer 3

Antibiotic resistance occurs when bacteria or other microbes builds the ability to resist the effects of the antibiotic. This happens when bacteria changes in a way that reduces or eliminates the effectiveness of the drugs designed to cure infections.

Answer 4

Effectively by natural selection.

When a stress is placed upon a population (the antibiotic) it will first kill the weakest bacteria, those which are most susceptible to the antibiotic. This leaves stronger bacteria behind to replicate. Resistance occurs due to errors in reading or replication of DNA causing changes to the bacteria, these less susceptible bacteria may have mutations in their DNA providing them with resistance. Over generations of replication as stress mutations accumulate leading to a stronger population which may be resistant

Answer 5

antibiotic resistance in bacteria occurs by 1) random mutations in bacteria, which, with a lot of luck, bring the resistance, 2) by exchange of "plasmids" between bacteria - an exchange of small DNA molecules which contain antibiotic resistance information, or 3) by "transduction" by viruses naturally attacking bacteria; these viruses, sometimes, with very little chance, can transport antibiotic resistance genes from one bacteria to another.

Answer 6

Consider a group of bacteria. They have slight genetic variances. When these bacteria are hit by a drug, say a standard antibiotic, most of them are killed off. Some might survive due to some mutation (perhaps additional pumps in their memberanes allow them to expel the antibiotic, providing additional protection). These few survivors remain and replicate. Pretty soon, you have a whole new population of bacteria- this time they're semi-resistant to the drug. Readministering the same antibiotic is going to be less effective- you'll just kill off bacteria which happen to get hit with an extra-strong dose or aren't as resistant. In the end, it means you're applying selective pressure so that the most drug-resistant bacteria are favored, and with every application of the drug, you're killing off fewer and fewer bacteria until the drug is rendered ineffective. The entire population of bacteria will have evolved resistance to that particular drug.

So then a different drug is tried, and will be able to wipe out these resistant bacteria-for now. Pretty soon, the bacteria will also develop resistance to that drug. Eventually, you end up with bacteria that are resistant to essentially every available drug- called "super-bugs". The only treatment for an infection of these are last-line of defense antibiotics, which tend to carry a greater risk of side effects for the patient due to their strength. Even now, many of the final option antibiotics are ineffective. Through constant research and new antibiotics we can buy more time to treat these super-bugs. Also, by reducing commerical uses of antibiotics, we can give bacteria fewer chances to develop resistance, which will hopefully translate to a longer period of effectiveness for conventional drugs.

Answer 7

Bacteria are able to develop resistance to antibiotics through the following methods:

• They are able to resist antibiotic action by denying it entry to the cell
• They may pump the antibiotic back out of the cell before it has had a chance to act, by means of enzymes called translocases.
• They may be naturally resistant to a particular antibiotic because they lack the target for its action OR have alternative biochemical pathways to cancel out its effect
• They may secrete enzymes that modify/degrade antibiotics
• Mutations may naturally occur that modify bacterial proteins

Answer 8

Antibiotic resistance is the ability of an organism to withstand the effects of antibiotics. It commonly arises due to natural selection caused by random mutation.