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Scientific Activity · The scientific method

Sources of Scientific Information

You get a video on WhatsApp saying that drinking water with lemon "cures any infection." Do you believe it? Before forwarding it, a scientist would ask several questions: Who is saying it? What evidence do they give? What do other sources say?

Primary and Secondary Sources

If you want to know what the Curiosity robot has discovered on Mars, you can read the original data it sent to NASA or watch a YouTube video that summarizes it with animations. How are these two ways of getting information different?

A rover on Mars produces data that a team publishes in an original article (primary source); a book, a video, and an encyclopedia summarize and explain that article (secondary sources). Primary source Secondary source summarizes Original article Book, video, encyclopedia

Wikipedia

Wikipedia is an encyclopedia written and corrected by thousands of volunteers. It is a secondary source: it does not present its own experiments, but summarizes what others have published.

Its risk is that almost anyone can edit it: an article may contain errors, be incomplete, be out of date, or lack sources. That is why it is not cited as the only source in a paper. Two strategies for using it well:

  • Check the references at the end of the article and read the original sources it points to.

  • Cross-check important data with another reliable source, such as an MINERD textbook or a university website.

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Look at the diagram: it distinguishes primary sources from secondary sources, but the four examples marked with "?" are waiting to be classified. Explain the difference…

Look at the diagram: it distinguishes primary sources from secondary sources, but the four examples marked with "?" are waiting to be classified. Explain the difference between a primary source and a secondary source, and classify the four examples from the diagram: a research paper in which a team describes its own experiment, a textbook, a popular science video, and an encyclopedia entry.

Scientific information PRIMARY SOURCE communicates its own results SECONDARY SOURCE summarises work published by others ? Research paper ? Textbook ? Popular science video ? Encyclopedia
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Explain what it means for a source of information to be reliable, and give two examples of reliable sources and two of unreliable sources for doing a science project.

Explain what it means for a source of information to be reliable, and give two examples of reliable sources and two of unreliable sources for doing a science project.

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Wikipedia is an encyclopedia written by thousands of volunteers. Explain whether it is a primary or a secondary source, what risks using it has, and two strategies for…

Wikipedia is an encyclopedia written by thousands of volunteers. Explain whether it is a primary or a secondary source, what risks using it has, and two strategies for making good use of it in a project (looking at the article's references, cross-checking the information in another source).

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Reliable Sources, Places Where Science Happens, and Plagiarism

A source is trustworthy (reliable) when we can count on it: it is signed by someone with training, it cites its data, and it is not trying to deceive you. For a science paper, good sources include an MINERD textbook, a scientific journal, the website of the Ministry of Public Health, or that of a university such as the UASD. Unreliable sources include a message forwarded on WhatsApp with no author or an anonymous blog full of ads.

Science is also done outside the white-coat laboratory: in universities, at the Museo Nacional de Historia Natural (National Museum of Natural History), at the Jardín Botánico Nacional (National Botanical Garden), in hospitals, in companies, or on the sea floor in Parque Nacional del Este (Eastern National Park).

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When you copy information from a website into a project without citing it, you commit plagiarism. Explain what plagiarism is, why sources must always be cited, and how a…

When you copy information from a website into a project without citing it, you commit plagiarism. Explain what plagiarism is, why sources must always be cited, and how a web page is noted down in the bibliography of a project.

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Scientists do not work only in white-coat laboratories. Name three places where science is done (a university, a natural history museum, a hospital, a company, the…

Scientists do not work only in white-coat laboratories. Name three places where science is done (a university, a natural history museum, a hospital, a company, the bottom of the sea...) and what type of research could be carried out in each one.

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How Science Is Communicated

When a laboratory develops an effective vaccine after months of testing, it does not start making it the next day: first it sends its work to other scientists so they can look for flaws. Why does science need to go through this collective examination?

Scientific publication process: a lab team submits its article, several independent experts examine it closely (peer review) and, if it is well done, it is published in a scientific journal. Team submits the article Peer review Published in a journal
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Scientific teams publish their results in journals and present them at conferences. Give two reasons why communicating results is an essential part of the scientific…

Scientific teams publish their results in journals and present them at conferences. Give two reasons why communicating results is an essential part of the scientific method.

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What is a scientific conference? Explain what research teams do there and why it is in their interest to present their results to other scientists.

What is a scientific conference? Explain what research teams do there and why it is in their interest to present their results to other scientists.

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Before being published, scientific papers undergo peer review. Explain what this process consists of and what assurances it provides to the rest of the scientific…

Before being published, scientific papers undergo peer review. Explain what this process consists of and what assurances it provides to the rest of the scientific community.

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Journals, Conferences, and Science Outreach

A scientific journal publishes articles written by specialists for other specialists, with methods, data, and references, and reviewed by peers. A news or entertainment magazine aims to inform quickly or entertain a general audience, without that quality control.

A scientific conference is a meeting where research teams present their results, receive questions and criticism, and learn about the work of others.

A scientific article and a science-outreach news story tell the same thing in different ways: the article is aimed at experts, uses technical language, and gives a lot of detail; the news story is aimed at the general public, uses simple language, and summarizes the essentials.

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Explain what a scientific journal is and how it differs from a news or entertainment magazine.

Explain what a scientific journal is and how it differs from a news or entertainment magazine.

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Point out two differences between a scientific paper and a popular science news story reporting the same discovery, thinking about the audience each is aimed at, the…

Point out two differences between a scientific paper and a popular science news story reporting the same discovery, thinking about the audience each is aimed at, the language, and the level of detail.

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Until 2006 books said the solar system had nine planets; since then they say eight, because Pluto was reclassified. Explain what this case teaches us about the…

Until 2006 books said the solar system had nine planets; since then they say eight, because Pluto was reclassified. Explain what this case teaches us about the importance of the date of sources and about how scientific knowledge changes.

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Open Access and the People Who Do Science

Many journals charge a subscription to read their articles. That is why there is a trend toward open access: publishing results so that anyone can read them for free. It is especially defended when the research was paid for with public money.

  • Advantages: more people (students, teachers, doctors in places with few resources) can consult the original data, and other teams can check and build on it.

  • Possible objection: publishing and reviewing an article costs money, and if the author pays, teams with less funding could have difficulty publishing.

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Choose a male or female scientist (for example, Margarita Salas or Severo Ochoa) and briefly summarise their contribution, an obstacle they had to overcome, and why it…

Choose a male or female scientist (for example, Margarita Salas or Severo Ochoa) and briefly summarise their contribution, an obstacle they had to overcome, and why it is important for people from all backgrounds to participate in science.

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Many public bodies require the results of research funded with public money to be published in open access, free for everyone. Give two advantages of this measure for…

Many public bodies require the results of research funded with public money to be published in open access, free for everyone. Give two advantages of this measure for society and one possible objection, and give your reasoned opinion.

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Evaluating Whether a Source Is Reliable

An internet article with four highlighted areas: the author's signature, the date, the list of references, and a commercial ad, which are the clues for judging whether a source is reliable. RD$ Buy Authorship Date References Interests
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You are looking for information about vaccines and find two websites: the official page of a health organisation, signed by specialists and with references, and an…

You are looking for information about vaccines and find two websites: the official page of a health organisation, signed by specialists and with references, and an anonymous blog full of adverts for "natural remedies". Explain which is more reliable by pointing out three specific clues (authorship, publication date, references, commercial interests).

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A headline announces: "Science proves that chocolate makes you slim". State three pieces of information about the original study that the news item should give in order…

A headline announces: "Science proves that chocolate makes you slim". State three pieces of information about the original study that the news item should give in order to judge it (who did it, with how many people and under what conditions, where it was published) and explain why each one matters.

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The same finding is headlined in one newspaper "A small advance could help treat Alzheimer's in the future" and in another "Miracle cure for Alzheimer's discovered!".…

The same finding is headlined in one newspaper "A small advance could help treat Alzheimer's in the future" and in another "Miracle cure for Alzheimer's discovered!". Compare both headlines: which devices the sensationalist one uses, what effect it produces on the reader, and which one fits real scientific work better.

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Interpreting Results with Caution

The results of an investigation must also be interpreted with caution. If in your school experiment (for example, lentils that sprout with music and others in silence) the plants grow the same in both cases, the hypothesis is not supported, and that is also a valid result.

Your conclusions should say what you were testing, what you obtained, whether the hypothesis is supported, and what limitations the experiment had (few seeds, little time, other conditions not controlled).

Likewise, a study of 25 athletes over two weeks does not allow the same conclusions as another with 2,500 adults followed for ten years. And a relationship between two pieces of data (coffee and heart risk) may be due to a third factor, such as smoking. If a company pays for a study that benefits it, you need to look more carefully at its design and at who funded it.

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A soft drinks company funds a study concluding that sugar does not contribute to obesity. Reason why this funding requires the study to be examined more carefully, and…

A soft drinks company funds a study concluding that sugar does not contribute to obesity. Reason why this funding requires the study to be examined more carefully, and name three things you would check regarding its design and who paid for it.

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You have found that lentils germinated while listening to classical music and others germinated in silence grow practically the same. Write the conclusions section of…

You have found that lentils germinated while listening to classical music and others germinated in silence grow practically the same. Write the conclusions section of your report (4-6 lines): what you were testing, what results you obtained, whether the hypothesis is supported, and what limitations your experiment has.

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Read the summaries of these two research studies on coffee consumption and cardiovascular health: • Study 1: Followed 25 athletes aged 20 for two weeks. They drank 1 cup…

Read the summaries of these two research studies on coffee consumption and cardiovascular health:

• Study 1: Followed 25 athletes aged 20 for two weeks. They drank 1 cup per day and their heart rate during exercise was recorded. Conclusion: coffee improves cardiac function.

• Study 2: Followed 2,500 adults between 50 and 70 years old for ten years. The group consuming more than 4 cups per day showed a higher cardiovascular risk; however, 70 % of the people in that group also smoked tobacco daily.

  1. a) Interpret both studies and justify why it cannot be claimed that one of them is lying: point out two fundamental methodological differences that prevent directly comparing their conclusions.
  2. b) What uncontrolled variable (or confounding factor) invalidates attributing the cardiovascular problems solely to coffee in Study 2? Justify your answer.
  3. c) Explain what procedure the scientific community follows (independent replication, rigorous control of variables, and meta-analyses) to reach a reliable consensus when apparent contradictions like this arise.
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Pseudoscience

On the internet you see ads for bracelets that promise to "align your quantum energy" and cure pain without explaining how they work or presenting trials in hospitals. How can you tell these products apart from real medical treatments?

Comparison between science (data graph, expert review, experiment repeated with the same result) and pseudoscience (bracelet with vague "quantum energy," user testimonials, and a price tag because it sells something). Science Pseudoscience evidence peer review can be repeated "quantum energy" empty technical language It worked for me! ★★★★★ testimonials RD$ sells something
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An advertisement sells a bracelet that "rebalances the body's energy" and is "endorsed by thousands of satisfied users". Identify at least three signs of pseudoscience…

An advertisement sells a bracelet that "rebalances the body's energy" and is "endorsed by thousands of satisfied users". Identify at least three signs of pseudoscience in this message and explain what evidence you would demand before believing its effects.

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Fake News and Myths

Fake news spreads fast on WhatsApp and social media because it appeals to emotions: "Share it before they delete it!", "doctors don't want you to know." Warning signs: it promises miracle cures, no professional signs it, it says "the pharmaceutical companies are silencing it," it relies on testimonials, it uses capital letters and exclamation marks, and it links to a store that sells the product.

When you get a message like the lemon one, ask yourself at least three questions: Who signs it, and are they a health professional? What evidence or studies does it cite? What do other reliable sources say? To check it, you can consult the website of the Ministry of Public Health or ask a doctor or your science teacher.

A typical case is the myth that "we only use 10% of our brain." It is false for biological reasons: the brain uses about 20% of the body's energy, and the body would not maintain such a costly organ if 90% of it were useless; in addition, brain imaging shows activity in all its regions, and an injury to almost any area causes some damage. And saying "no one has proved it is impossible" is a bad argument: whoever makes a claim is the one who must provide the evidence.

Back to the beginning: the water-with-lemon video cites no reliable studies, is not signed by any health professional, and promises magic cures: it is fake news that you should neither believe nor forward.

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A video circulating on social media claims that drinking lemon water "cures any infection". Write at least three questions you should ask yourself to check if the…

A video circulating on social media claims that drinking lemon water "cures any infection". Write at least three questions you should ask yourself to check if the information is reliable, and name two sources where you could verify it.

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On a social network, you find this post: "The definitive cure for the flu that pharmaceutical companies are keeping quiet! Take two spoonfuls of our wild herbal blend at…

On a social network, you find this post: "The definitive cure for the flu that pharmaceutical companies are keeping quiet! Take two spoonfuls of our wild herbal blend at the first symptom and you will eliminate the virus within 24 hours. Backed by thousands of real testimonials." The account does not show the name of any healthcare professional and links to an online store where a bottle costs 35. pesos

  1. a) Identify at least three red flags in the message that prove it is a hoax or pseudoscience rather than reliable medical information.
  2. b) Justify why testimonials from satisfied users are not valid as demonstrative scientific evidence.
  3. c) Design a three-step strategy you would follow to check the truthfulness of that claim before giving it credit or sharing it (sources you would consult, search terms, and cross-checking the information).
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A very popular documentary states: “Humans only use 10% of their brain capacity; if we managed to activate the remaining 90% through mental training, we would have…

A very popular documentary states: “Humans only use 10% of their brain capacity; if we managed to activate the remaining 90% through mental training, we would have extraordinary abilities such as telepathy or photographic memory.” The author claims that his hypothesis is valid because “no one has proven in a laboratory that it is impossible to use more than 10%.”

  1. a) Refute this myth by providing two biological arguments based on the functioning of the body: one related to the high energy consumption of brain tissue (it consumes about 20% of the body's total energy) and another with medical observations regarding brain injuries.
  2. b) In scientific research, the principle of the “burden of proof” applies. Explain what mistake the author makes when stating that his hypothesis is valid as long as the contrary is not proven.
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An Example of Organized Knowledge: The Kingdoms

When you look at a textbook or an encyclopedia, the knowledge already comes organized by scientists. A good example is how the enormous diversity of living things is organized: how do you order millions of species so they can be studied?

All living things share traits that set them apart from nonliving matter: they take in nutrients, interact with their environment, and reproduce. To study their diversity, scientists classify them into groups called kingdoms, according to cell type, number of cells, and way of obtaining nutrients.

Kingdom Cells Nutrition Dominican example
Monera prokaryotic, unicellular varied yogurt bacteria
Protista eukaryotic, mostly unicellular varied microscopic algae
Fungi eukaryotic absorb food bread mold, yeast
Plants eukaryotic, multicellular photosynthesis mangrove, mahogany, royal palm
Animals eukaryotic, multicellular consume food manatee, solenodon, palmchat

To identify which group a living thing belongs to, identification keys are used: a series of questions with two options ("Does it have an internal skeleton? yes / no") that rule out groups one by one until you reach the right one. You can find these classifications in reliable secondary sources, such as textbooks or the websites of the Jardín Botánico Nacional and the Museo Nacional de Historia Natural. And, like any scientific knowledge, they can change when new data appear.

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Write the "materials and method" section of the report of an experiment on the effect of light on lentil germination, in such detail that another group could repeat it…

Write the "materials and method" section of the report of an experiment on the effect of light on lentil germination, in such detail that another group could repeat it without asking you anything. Then explain why science demands that level of detail (reproducibility).

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Summary

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