The Cosmos video we watched explains the different types of evolution that can occur, one being artificial and the other one being natural selection.
Artificial selection happens when humans interfere with the way animals evolve by breeding them between species, etc. We can see this from the evolution of dogs from wolves. Humans bred animals and plants so that they can exhibit a particular trait desired that usually helps them survive. We can see this happen until today when tomatoes were artificially evolved to have a natural pesticide. Natural selection happens without the interference of humans, meaning that they happen by themselves in nature. The genetic material of each species determines which environment is best suited for them. Both these types of evolution happens for many generations and competition between species helps largely affects the process of natural selection. Another type of evolution this video explained is why evolution occurs from genetic mutation as well as nature taking part in the process of natural selection.
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What is Evolution?
According to the dictionary, evolution can be defined as "the process by which different kinds of living organism are believed to have developed from earlier forms during the history of the earth". In other words, evolution is the idea that life adapts to the change that constantly happens around the world. What is the difference between Fact and Theory? A fact is an observation that has been confirmed several times by science, therefore accepted as "true" by the scientific community. For example, an easy fact that we all know is if we throw an object into the air, it will inevitably fall back to the ground. Theory is an explanation of some aspects of the world that is backed up by facts, tested hypotheses, and laws. Theories aren't proven with 100 percent certainty, therefore it is backed up by many sources. An example will be Einstein's Theory of Relativity. How do species evolve? A website named FactMonster stated that: "A species is a group of similar living things, such as lions, that can breed together. If a group of individuals within a species becomes separated from all the other groups of that species, they can no longer breed with them. In time, the group evolves separately and becomes increasingly different. Eventually, it is so different that it becomes a new species". In other words, if a species is separated from its other similar living things, the group will evolve and become much different from what they originated from. Sources: https://www.factmonster.com/dk/encyclopedia/nature/evolution Columbia University's Mailman School of Public Health stated that:
"Scientists at the Center for Infection and Immunity (CII) in the Columbia University Mailman School of Public Health have developed the first diagnostic platform that can simultaneously screen for all known human pathogenic bacteria as well as markers for virulence and antibiotic resistance. A study in the journal mBio provides details on the performance of the BacCapSeq platform." (quoted directly from the article) Bacterial infections can prove to be very dangerous. Every year, infections resistant to antibiotics claims over 700,000 lives around the world, 100,000 of which are from the US alone. Not only is it devastating to the population, it is also devastating towards the economy. The impact of antibiotic resistance on the US economy is estimated to be $20-35 billion with an additional $35 billion lost in productivity. These are used for the upkeep of the antibiotics. Furthermore, the World Bank issued a report in 2017 projecting the impact of antibiotic resistance on the GDP to be between $1.1 trillion and $3.4 trillion. Because of this, scientists created a diagnostic platform known as "BacCapSeq". The platform contains 4.2 million genetic probes used to detect the signature DNAs of all the 307 pathogenic bacteria, which can be used for antibiotic resistances. They work by binding to a corresponding sequence. When a particular bacterium and biomarker is present in a sample, the unique sequences are pulled out by a magnetic process, which can then be used to identify the bacterium and its characteristics. This is a major breakthrough in biological research since it helps identify the pathogenic bacteria which makes it easier to pinpoint the antibiotic resistances needed. https://www.sciencedaily.com/releases/2018/10/181023085646.htm Since the file is too large for Weebly, the file is in this Google Drive folder. It contains the word document and a PDF version as well.
https://drive.google.com/drive/u/0/folders/12_6W8Hp0io27lI40X6QzkG67qjNvOlFI For me, I compare the cell to a country. The reasons are the following:
1. Nucleus - Government This is because the government controls everything that is happening inside the country. Inside the nucleus is the nucleolus which houses the DNA. The DNA controls everything going on in the cell, therefore I compare them to the people working in the government. 2. RER - Highways The Rough Endoplasmic Reticulum (RER) transports and stores items going around the cell such as polypeptides and proteins. The highways connect organisations and people among the country so the government can govern people around the country easier. The items sent can be compared to orders from the government to other existing bodies. 3. SER - Border Guards and Construction The Smooth Endoplasmic Reticulum creates lipids which are used for producing new cellular membranes. I compare this to the Border Guards and Construction because this helps reinforce the cell membranes which organise what goes in and out of the cells. 4. Mitochondria - Agriculture and Food Sectors. The Mitochondria generates energy for the cell. This is why I compare them to the food sectors in a country. A country needs people to run it and people need food to keep being fit. That is where the food sectors create food for the country. 5. Golgi Apparatus - Shipping Sectors The Golgi Apparatus is responsible for transporting, modifying, and packaging proteins and lipids to their target destinations. This is why the Shipping Sectors are the most closest to their function. The Shipping Sectors are the ones responsible for delivering items across the country such as food, water, raw materials, etc. 6. Ribosomes - Factories The Ribosomes converts information carried in the genetic code to protein molecules. since protein is the base of everything in the cell, therefore it can be compared to factories. Factories process raw minerals and create them into something that is usable by every part of the country. 7. Cell Membrane - Border Guard The Cell Membrane controls what goes in and out of a cell, just like what border guards do. They regulate people and goods coming from outside the country to keep the country safe from disease or from problems originating from the outside. Plants Only / Significant 8. Chloroplast - Raw Food Sectors The chloroplast is the site of photosynthesis for the cell, therefore it collects the sunlight that will be converted into food. The sectors specialising in collecting raw food will fit because these sectors create food that will be processed into different products. An example is they collect cows which can later be processed into beef, milk, cheese, dairy products, etc. 9. Vacuoles - Storage Units Despite them being in animal cells, vacuoles are more significant in plant cells. The vacuoles store excess food in the cell. This is more needed in a plant cell since they generate their own food. Storage units also store excess foods or other materials. Extra food can later be used and it can prevent the country from failing when food is getting harder to collect. 10. Cell Wall - Extra Border Guards The Cell Wall is like an extra layer protection against dangerous organisms. That is why it means that it is just like extra border guards. They regulate what goes in and out of the country, letting safe people or goods through but keeping the dangerous ones out. 1. How did Janssen's, Hooke's, and Leeuwenhoek's work contribute to the work of the scientists that came after them?
Zacharias Janssen found the microscope in 1595. Immediately, other scientists made improvements on the microscope. Janssen paved the way for many more discoveries regarding to microbiology such as cell structure, microorganisms, and pathogens. In addition, many more variations of the microscopes have been made. For example, dissection and confocal microscopes. Robert Hooke discovered the cells in 1665. He was able to study tree barks and saw that they looked like jail cells, therefore naming them cells. This means that the term we have been using originally came from him and it opened the way to the discovery of organelles, DNA, etc. Antony van Leeuwenhoek discovered bacterias in 1676. He discovered "protozoa" which is the single-celled organism and named them "animalcules". Therefore, he laid foundation for microbiology and paved the way for more discoveries. 2. How would our lives be different if we had never realised the existence of microorganisms? Provide at least one example to support your answer. If we never realised the existence of microorganisms, then we could never have found diseases or pathogens. These organisms are too small to see by the naked eye. Because of this, many new diseases could emerge and threaten the human race. An example was the Black Plague. Back during the 1350's, microscopes didn't exist and they can't see the pathogen that was very lethal to the human body. Because of this, there were deaths estimated to range from 75 to 200 million. 3. Describe the concept of spontaneous generation. Why do you think it took such a long time for people to accept that this idea was incorrect? Spontaneous generation is a concept made to explain why things appeared out of "nowhere". This theory was made by Aristotle during the 4th Century BC. This concept was around before the discovery of microscopes, but stayed until the 19th Century. Organisms that people believed emerged from spontaneous generation include 4. How do you think the cell theory impacted later scientific discoveries? Explain your answer. The cell theory impact modern scientific discoveries because scientists can have a better understanding of organisms. Scientists can better understand organisms and where they come from such as cells, etc. Another benefit from the cell theory is that we can understand more about diseases because we know viruses and bacterias from the theory. 5. The microscope and numerous experiments lead to the rejection of spontaneous generation. This idea had been accepted by most people, including scientists, for over 200 years. How does this demonstrate the true nature of science? The true nature of science is that it always changes. Science has always developed according to human discoveries. Another example of this is the discovery of atoms. When John Dalton first discovered it, he thought it was just a circle. Later, Thomson found electrons followed by Rutherford who found the nucleus and protons. 6. Review Pasteur's experiment. Relate his experiment to the scientific method. a. What was Pasteur's question? Pasteur's question was "Where do the microbes come from to cause broth to decay?" Most of the people back then believed in spontaneous generation, this means they believed that the microbes appear from the air. b. State a reasonable hypothesis based upon this question. Pasteur did not believe in spontaneous generation. His hypothesis was "Microbes come from cells of organisms on dust particles in the air; not the air itself." The experiment that he did was to prove that his hypothesis was right. c. What was the independent variable in Pasteur's experiment? What was the dependent variable? The independent variable in Pasteur's experiment was the curved neck of the flask, whereas the dependent variable would be the broth. The cloudiness of the broth would indicate if it was contaminated or not. d. What did Pasteur conclude from his experiment? Pasteur concluded from his experiment that his hypothesis was right. The curve-necked flask wasn't contaminated because the microbes was stuck in the neck, whereas the straight flask was contaminated because the microbes could get down easily. 7. Examine your timeline. How long did it take to develop the cell theory? What does this imply about the formulation of a theory? If we look at it since the first discovery of cells, it took 190 years for the cell theory to fully develop. But, if we were to see it from the first cell theory until the third part was added, it took 16 years to finish the theory. The timeline is as follows: 1. 1665, Robert Hooke first observed the cells 2. 1670, Leeuwenhoek observes the first living cells 3. 1683, Leeuwenhoek observed the first protozoa and bacteria was discovered 4. 1833, Robert Brown discovered nucleus in plant cells 5. 1838, Schleiden proposed all plant tissues are composed of cells 6. 1839, Schwann created the Cell Theory 7. 1840, Roelliker discovered sperm and egg cells 8. 1845, Heinrich Braun proposed cells are basic units of life 9. 1855, Virchow added the third part of the Cell Theory (all cell develop from existing cells) 8. Why do we still consider the cell theory a theory? Explain your answer. We still consider the cell theory as a theory because we still cannot prove how cells are formed. We can only assume that they are made from other pre-existing cells, but we do not know where those pre-existing cells come from. Other than that, the cell theory is as stated before just an assumption, same like the Quantum theory, Einstein's Theory of Relativity, and the Theory of Evolution. These theories are only assumptions of the laws of the universe. |
KirizyuA student from Sekolah Highscope Indonesia, Wants to be a robotics engineer. |