Exercises: Sources of scientific information

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.

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 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.

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

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.

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.

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.

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.

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.

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.

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.

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).

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).

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.

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.

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.

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.

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.

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.

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.

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).

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.

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.

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.

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).

Unit challenge. How does the thermal comfort of your home respond compared to the outdoors? Become a scientific researcher and prepare a brief report following these phases:

1. Question and hypothesis: Formulate a testable hypothesis about whether the thermal oscillation inside your house is at least $4,0$ °C smaller than the outdoor oscillation. Check and record the forecasted data for your town/city on the official AEMET website to contextualise your environment.

2. Observation and measurement: Measure and record the indoor and outdoor temperature for two consecutive days at three times: $8{:}00$, $14{:}00$, and $20{:}00$ h, noting the values with decimal precision (for example, $19,5$ °C).

3. Analysis and communication: Organise the measurements in a table, draw a comparative line graph, and write a conclusion that confirms or rejects your hypothesis, formally citing the official source used.

Assessment criteria:

• Rigorous application of the stages of the scientific method, from the hypothesis to the conclusions.

• Precision in empirical data collection and formal correctness of the table and graph.

• Proper use and citation of reliable scientific information sources (AEMET).

• Critical ability to argue the results and identify possible biases or errors.