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Penicillin Script
Hi. Good morning everybody. How are you? I want to talk to you about penicillin today. First though, don’t forget, if you click on the link in the about section below here, you can find the script for this talk and you can find the … you can find some questions and you can find sample answers and things like that. Have a look. If you like this, subscribe, like, all that kind of stuff.
So, penicillin. What is penicillin? Well, basically, penicillin is an antibiotic. It’s one of the group of antibiotics. What do antibiotics do? Well, they kill bacteria, basically. So, to talk about penicillin, of course, we have to start by talking about bacteria. What are bacteria? Bacteria, of course, are single celled organisms. Bacteria are generally a few micrometers long, which I cannot do with my fingers of course, because that’s tiny. You cannot see them with the naked eye. There are many, there are trillions … there are quintillions of bacteria in the world. You have about 39 trillion bacteria inside your own body, and they live in your stomach, most of them. What they do is, they help break down the food that you eat. Without those bacteria breaking down the food in your stomach, you couldn’t process all of the food. You would have to pass it pretty much solid, and you wouldn’t be able to extract the nutrients and the sugars, and all the good things from those foods. So, we need bacteria.
Of course, there are bacteria outside. One gram of soil apparently has about forty million bacteria in it, and without those bacteria, anything that died, plants or animals, would just lie there on the ground. We need those bacteria again to break down the things that die into their component parts. So, they can be eaten, or absorbed, or released back into the atmosphere as nitrogen. So, we need bacteria. Without bacteria we couldn’t survive. We couldn’t have life as we know it today. And there are good and bad bacteria, of course. Actually, no, there are not good and bad bacteria, because that implies that bacteria have intentions, which of course they don’t. There are bacteria that are useful to us, and there are bacteria that are harmful to us. That’s probably a better way of putting it.
Bacteria, of course, replicate themselves. They replicate using a process called binary fission. Basically, they reproduce their D.N.A. and then they split into a new cell, reform their cell walls, and you have two bacteria. And again, those two bacteria can reproduce, and reproduce, and they can reproduce exponentially. So, two, four, eight, sixteen, thirty-two, sixty-four and so on. In perfect conditions, a bacteria, a bacterium, can reproduce itself every 9.8 minutes. So, if you think about that, you can imagine how quickly they can reproduce.
Some bacteria that are harmful to us, bacteria that destroy tissue, like after a wound, if you get an infection. Bacteria, because they reproduce, they can become too numerous. They can overwhelm parts of your body. Bacteria also produce toxins as well, when they’re alive and when they’re dead. Those can also be harmful to us.
As a slight aside, some people like to think that life on earth could have become … begun with bacteria. Life on Earth could have begun with bacteria that traveled on a meteorite from a different planet, from even a different universe. Bacteria are some of the hardiest beings … beings? … creatures … living organisms on Earth. You have bacteria in extreme cold, extreme hot. At the bottom of the sea, some of the hot vents down there, We have extremophiles, bacteria that live in those conditions. So, some people think that bacteria could have survived an interstellar journey and life on earth could have actually begun with bacteria from a different universe, from a different world, which is a nice way of thinking about it. We are all aliens.
So, if you get a bacterial infection say, or say, for example, food poisoning or an infected wound, what happens? Well, your body has to kill the bacteria. How does it do that? Your body produces white blood cells. There are different kinds of white blood cells, but the kind that kill bacteria, there are two sorts. One of them hunts down the bacteria and puts a protein marker on it. So, they find the bacteria. And the second type of white blood cell, they follow those protein markers and basically hunt down the white … they basically hunt down the bacteria and they kill them. They surround them, and they basically eat them. Now, obviously, if you have a very severe bacterial infection, if you have a lot of bacteria, the white blood cells cannot eat all of those bacteria. You have some left over, and that’s when, of course, bacterial infections can kill you. That’s when you need help, outside help of course. But, when your body produces white blood cells to go and hunt down these bacteria, it also does a few other things to help protect you. One thing of course, is you get a fever. When you get sick, you have a fever. Many people think that’s an awful thing, but actually, that is your body trying to fight this bacterial infection. Bacteria and viruses can only survive in a certain temperature zone. So, what your body does is, it raises its internal temperature to try and kill off these bacteria. So, next time you have a fever, your body is actually trying to save you by heating you up, because you can survive high temperatures that the bacteria cannot. Isn’t that awesome? Another thing that’s also amazing is, when the white blood cells kill these bacteria or viruses, they actually … a few of the white blood cells … actually remember that bacteria. So, next time you have the same bacterial infection, your body can hunt it down and kill it much faster. Your white blood cells actually remember a type of bacteria! Isn’t that awesome? And that’s actually how immunology works. If you have a flu shot, or if you have an injection against a certain type of bacterial disease, what that is doing is introducing a small amount of that disease into your body so that your white blood cells can remember that disease. You’re basically programming your body to fight diseases. That’s absolutely awesome! I mean, I knew that the flu vaccine, that vaccinations worked, I didn’t know how they work. That’s quite incredible. Our bodies can be programmed.
Anyway, so, antibiotics, they stop bacteria. They kill bacteria. How do they do that? What they actually do is, the antibiotic attaches itself to the bacteria and it stops the bacteria building its cell wall. So, when the two bacteria … when a bacteria splits into two, it has to obviously recreate its cell wall, and the antibiotic stops it doing that. Yhe cell wall is called the peptidoglycan. So, because the bacteria cannot reproduce that cell wall, basically it dies. It needs its cell wall in the same way you need your skin to stay alive. So, bacteria can harm humans and antibiotics can stop bacteria, so antibiotics are an extremely useful source. Our bodies cannot kill all the bacteria, so we use antibiotics to kill the bacteria that we ourselves cannot kill.
So, where did antibiotics come from? Well, how did we discover antibiotics? You probably know the famous story. Alexander Fleming, Friday 28th September 1928, first discovered penicillin. How did he do it? He had a petri dish full of a type of bacteria he left out overnight and the window was open. And when he came down in the morning, mold from outside had come into the petri dish. And when he looked at the petri dish, he noticed that where the mold was there was a space between the mold and the bacteria. So, something in the mold was actually preventing the bacteria from growing. Now, he needs to know, so he analyzed that. He did a lot of tests of course, and he worked out that only one kind of mold, the penicillin mold, worked. So, the penicillin mold … something in the penicillium mold was stopping the bacteria growing. It was inhibiting the bacteria. And obviously, he realized the huge ramifications, huge implications of this. However, Alexander Fleming was a notoriously poor communicator. He was very bad at speaking to people. He was your stereotypical scientist. He was excellent in the lab, he was an amazing chemist, but he was not so good at communicating his ideas. So, when he discovered this penicillin, when he discovered the effect penicillin has on bacteria, he tried to tell people, but nobody would listen. Nobody would believe him. Nobody would read his reports. He couldn’t get anybody to try to replicate it. He couldn’t get anybody to try and produce it. So, for a few years, nothing happened. Then, luckily, 1930, a man called Cecil George Paine, he had heard of these experiments, and he tried to use penicillin to cure an eye infection in one adult and two children. And that actually worked. Because of him, news of penicillin started to take off. Then, in 1940, a man called Howard Florey and Ernst Boris Chain, they’d worked out how to mass produce penicillin, and they took this information across to America.
Then, of course, what happened in 1941? World War Two breaks out. Well, World War Two is already going on. In 1941, America joins World War Two. This is probably the most important date … the most important period in the development of penicillin. Why? Because in a war, most people that die don’t die from being shot, they don’t die on the battlefield. They die after the battle. They die of war wounds. They die of infections. They die of disease. For example, if you look at the U.S. Civil War, 1861 to ’65, for every three people that were killed on the battlefield five people later died of disease. Depending on the war, approximately 70% of people … of casualties … are caused by disease, by infection. And, what is infection caused by? It’s caused by bacteria. How can you stop bacteria? Penicillin. In the beginning of 1941 there was enough penicillin in the world for about ten people. By the end of the Second World War, June 1945, the American government was producing 646 billion doses of penicillin every year. Thanks to the Second World War, the production of penicillin exploded. And thanks to the Second World War, we now have penicillin for everybody. If the Second World War had not happened, who knows how long it would have taken for penicillin to be developed. People always say war is bad, and of course war is bad, but a lot of good things do always come out of a war. (That could be an interesting topic later on.)
Anyway, 1945, after the Second World War, Fleming, Florey and Chain, they were all given the Nobel Prize for Chemistry. For the things they did for chemistry. And, thanks to them, we have penicillin as we have it today. However, as you may have heard, antibiotics are being used to fight bacteria all over the world. A lot. We take a lot of penicillin every year. We take a lot of antibiotics every year. And it does work of course. However, bacteria evolve. And this is absolutely amazing. This is … I mean this is proof of evolution. Bacteria evolve to cope with antibiotics. So, an antibiotic that used to stop the bacteria growing its cell wall now doesn’t work. We have to constantly try and produce different kinds of antibiotics to fight these new and growing bacteria. Who knows? At one point in the future, we may have bacteria that we cannot treat, and we’ll have to think of other ways. Nanorobots might be a good way. You send nanorobots in to actually physically kill the bacteria. And that’s probably not far in the future. (There’s another topic there I think for a talk.) So, bacteria evolve. Bacteria reproduce themselves, but, occasionally mutations appear. And these mutations make the bacteria stronger to an antibiotic, which of course is an advantage, which means that advantage is then passed on. And the bacteria that are killed by the antibiotic die out, and the bacteria that are resistant to the antibiotic survive, and replicate, and reproduce. And there you have evolution in a nutshell. A perfect example of evolution.
Anyway, so thanks to Alexander Fleming, but possibly more than that, thanks to the Second World War, we have antibiotics as we know them today. However, they are becoming outdated and soon we will have to think of a new thing.
Anyway, thanks for listening. Thanks for watching. I hope you understood this. As I said before, if you click the link down there, you can see the script and you can see questions for this and you can also see some sample answers. If you liked it click like. If you want to subscribe, that’s somewhere over here. It looks like my face. Please subscribe. Thank you. I’ll see you again next week. Have a nice week. Bye.
Penicillin Questions
- How long is a bacteria?
A: 0.002 mm
B: 0.020 mm
C: 0.2 mm
D: 2 mm
- What do the bacteria in your stomach do?
A: They get attacked by white blood cells.
B: They make you sick by releasing toxins.
C: They break down the food you eat.
D: They help you get over illness.
- What is binary fission?
A: It is the process by which white blood cells kill bacteria.
B: It is the process by which bacteria reproduce.
C: It is the process by which our stomachs break down food.
D: It is the process by which bacteria enter our bodies.
- Why do some people think life on Earth could have been seeded by bacteria on a meteorite?
A: Because bacteria like to travel through space.
B: Because bacteria can only be killed by penicillin.
C: Because bacteria can reproduce exponentially.
D: Because bacteria can survive in very difficult conditions.
- Why do white blood cells put a protein marker on the bacteria?
A: So that the bacteria’s cell wall breaks down.
B: So that other white blood cells can hunt them.
C: So that we don’t have to use antibiotics.
D: So that they can use the bacteria to help the body.
- Why do you get a fever when you have a viral or bacterial infection?
A: Because if you sweat a lot you can rid your body of bacteria and viruses.
B: Because bacteria and viruses can only survive at a certain temperature.
C: Because it makes you sleep, and sleeping is the best thing when you are sick.
D: Because white blood cells work better in a hot environment.
- How does a vaccination work?
A: You are injected with antibiotics that proceed to attack all of the bacteria in your body.
B: A small amount of the disease is introduced into your body and your white blood cells remember it.
C: White blood cells are injected into your body.
D: A small amount of protein markers are introduced into your body to track down bacteria.
- What accident helped Alexander Fleming discover penicillin?
A: He left a petri dish in his laboratory.
B: He left some mold by a petri dish.
C: He left a window open.
D: He left some penicillin by a window.
- Steven says, “He was your stereotypical scientist.” Which of these sentences is closest in meaning to that?
A: Fleming was not good at writing up the notes for his experiments.
B: Fleming was instrumental in the design of the radio.
C: Fleming was good at research but not interacting with people.
D: Fleming was part of the group who would win the Nobel Prize.
- What killed most people in the American Civil War?
A: Bullets.
B: Infection.
C: Lack of money.
D: The type of doctor.
- How many doses of penicillin were being produced by the US government by the end of WW2?
A: 646,000
B: 646,000,000
C: 646,000,000,000
D: 646,000,000,000,000
- Bacteria becoming resistant to antibiotics is a good example of what?
A: Ambition.
B: Pollution.
C: Revolution.
D: Evolution.
- How would nanotechnology be beneficial to the treatment of diseases?
- If all diseases were cured, what would happen to the world’s population?
- Will doctors be replaced by AI?
- Wars are increasingly being fought by autonomous machines. What do you think about that?
- What do you think the next step in human evolution will be?
Penicillin Questions Answers
- A 2. C 3. B 4. D 5. B 6. B 7. B 8. C 9. C 10. B 11. C 12. D
- How would nanotechnology be beneficial to the treatment of diseases?
Nanotechnology presents a huge advantage over regular cures for diseases because it is targetable and controllable. Nanorobots would be the size of a bacterium, or even smaller, and they would permanently live in our blood streams. If we were to catch a cold, or a bacterial infection, the nanorobots would activate and they would hunt down the offending viruses or bacteria. They would not only be faster than our body’s own immune system, they would work in tangent and clean up all the organisms that our white blood cells couldn’t catch. We would be able to get over colds before we even knew that we had one. A greater advantage, though, is the ability to target diseases that our immune system cannot fix. Cancer is a good example of this. Cancer occurs when cells in your body start to reproduce too quickly. Your immune system can fight it, but often the cells are too numerous and spread too quickly. One of the main treatments for cancer is chemotherapy, where toxins are used to kill the cancer cells. However, it is impossible to direct the toxins at the cancer cells and many of the good cells in your body absorb toxins too. This can make a patient ill and leave many cancer cells alive. If nanorobots were introduced into a patient’s blood, they could be tasked with carrying the toxins directly to the cancer cells. All of the cancer cells would be killed, and no good cells would be harmed. A perfect solution.
Despite the many advantages, there are also some disadvantages. One of these is the potential for nanorobotic disease. Terrorists, or belligerents in a war, could engineer nanorobots to create disease. Introduced into the water, or food source, it would be technically possible to kill millions of people. Another disadvantage would be the impact to the natural balance of nature. Were the nanorobots in your body to be released into nature, they could very well kill necessary bacteria.
Nanorobots will be a part of the future, however a lot of thought needs to be put into their safe usage.
- If all diseases were cured, what would happen to the world’s population?
That is an interesting question. For the sake of argument, I am going to assume that people still die, just at a much later date. There are three possibilities that I can see. The population would stabilize, it would keep rising, or it would be stopped by an event.
The population would age and stabilize. If people do not die of disease, and their life expectancy increases to two or three hundred years, they will either have very few children or no children at all. After a while the birth rate and the death rate would cancel each other out and the population would stabilize. However, if this happened, the population would be extremely unbalanced, with most of the people in the middle.
The population would keep rising. Technically, there is a limit to how many people Earth can support. However, as technology advances, this number will rise. Currently, it would be difficult to produce enough food for more than 11 billion people (a number that could be reached by 2100), however, as genetically modified food, 3d printed food and lab created food take off, this problem could disappear. Drinking water would also not be a problem if desalinization plants improve. Our carbon footprint and the damage we do to Earth would worsen, but technology could potentially solve this as well. In theory, Earth could support a very large number of people.
The population would be stopped by an event. As all disease has been cured, this event would either have to be man-made or extraterrestrial. If people are living for a few hundred years, but a large percentage of the world still live in poverty, war could become likely. A war of the future may easily wipe out 70% of the world’s population. A meteorite strike would also lower Earth’s population. Alien invasion, although unlikely, could also reduce the population.
Out of these three possibilities, I must say that the first seems the most likely. As the world advances, the standard of living around the world will equalize. People who live in wealthier countries tend to have fewer children. This is why most developing countries have an aging population. If people live far longer, I see the birth rate declining until the population falls for a while and then stabilizes.
- Will doctors be replaced by AI?
In a word, yes. Doctors spend countless years learning how to read the human body and diagnose diseases as and when the occur. A specifically programmed AI unit could do the same job. On top of that, doctors make mistakes in diagnosis that self-learning AI systems wouldn’t. Doctors will say that their job is more than just diagnosis, and they are right, but the number of doctors and people’s access to them is limited. The advantages of a medical AI system would far outweigh the advantages of doctors. Then, if technological progression continues, AI nanobots would be in our blood streams and they would fix all injuries or diseases as soon as they appear. There are many jobs that will be replaced by AI over the next few decades, and the medical profession is probably one of them.
- Wars are increasingly being fought by autonomous machines. What do you think about that?
I believe that the disadvantages outweigh the advantages, although, we have passed the tipping point and this kind of technology will only increase.
Let’s begin with the three main advantages. The obvious advantage is that autonomous machines in a war reduce the number of human casualties. Machines are replaceable and cost less to outfit than a person. And machines are tireless. These three reasons alone mean that the development of autonomous machines will increase.
However, there are numerous disadvantage. The first is that autonomous machines cost a lot to develop. Only wealthy countries can afford to develop them, and that will give a huge lead over poorer countries. The world’s rich poor gap would only increase. Secondly, distance removes feeling. Autonomous machines, such as drones, are operated by a controller far away. In war, facing the enemy in front of you, you can choose to kill or not. You can feel the emotion, you can feel your humanity. Operating from thousands of kilometers away makes war just a computer game. And, thirdly, it is dangerous. Currently, the US has a machine that can select its own targets. If these machines become the main, how do we control who they are targeting. How do we stop them targeting us?
Technology never goes backwards. Once a development has been made, we have to adapt too it. These autonomous machines are already here, and we have to learn to live with them. However, a great amount of care needs to be taken.
- What do you think the next step in human evolution will be?
The next step in evolution is going to be technological. Evolution takes place over thousands of years, for the most part, however, technology is advancing exponentially at the moment. The next step in evolution will be implants and additions that improve the capability of our own bodies. Improved eyesight, hearing, memory capacity, strength, speed, stamina. We will become a far superior species. At some point, we could even become more machine than human. A scary, or exciting concept.