A biological problem means scientists have questions about things in nature, like the environment or health. They use the same way to find answers, which involves gathering evidence using logic to support their ideas. For example, people used to think malaria was caused by "bad air", but a scientist found out it is actually spread by mosquitoes. This helped solve the problem of what was causing malaria, which is a disease that has killed many people for a long time.
To solve a biological problem, you need to first figure out why there's a problem and ask a question about what you see. Start by observing things like how plants move or how animals behave. You can observe things by using your senses i.e. qualitative observation or scientific equipment i.e. quantitative observation. The knowledge you gain can be from what you see, hear, feel, or measure.
In 1880, a French physician, Laveran, studied the blood sample of malaria patient under microscope and observed tiny creatures in it and named as Plasmodium. So the observation was made that Plasmodium is present in the blood of malaria patients.
A hypothesis is an important part of the scientific process. It is an intelligent guess made by a scientist in the form of a statement. It's essential that a hypothesis can be tested, which means you can check if it is true or false by experimenting. After you test your hypothesis, you will know if it's supported (true) or not supported (false).
In the case of malaria, an intelligent guess is made after observation that Plasmodium is the cause of malaria. But it is only a guess which can be presented as a hypothesis.
Biologists use two types of reasoning to come up with a hypothesis: inductive reasoning and deductive reasoning.
Inductive reasoning starts with specific examples and then draws a general conclusion. For example, if all fishes have scales and a shark is a fish, then a shark must have scales too.
Deductive reasoning starts with a general idea and then makes a specific prediction based on that idea. Deductive reasoning can be tested and verified through experiments.
In the case of malaria, the following deduction is made: “If Plasmodium is the cause of malaria, then all the malaria patient should have Plasmodium in their blood”.
After observing a problem and suggesting a hypothesis, scientists then design experiments based on their reasoning to identify the real cause of the problem. The experiment is a practical test that can be repeated many times by other scientists to confirm the results.
Scientists perform two types of tests i.e, control group and experimental group. To find out the cause of malaria, blood samples of 100 malaria patients (experimental group) and the blood samples of 100 healthy persons (control group) were examined under a microscope.
The results are where you tell what happened in your experiment. You share all the things you observed and measured during the experiment. The results help prove or disprove your hypothesis.
All the malaria patients (experimental group) had Plasmodium in their blood. The blood samples of healthy persons (control group) were free from Plasmodium.
The last step of the scientific method is to draw a conclusion based on the results of your experiment. This means analyzing what you found out and deciding if your hypothesis was correct or not. If your hypothesis was supported by the experiment, it means you found an answer to your question. However, if it wasn't supported, you can try conducting the experiment again or modifying your methods to see if you can get a different result.
Conclusion is made that “Plasmodium is the cause of malaria”.