Unit 1 lesson 1 What is Science

Unit 1 Lesson 1 What Is Science?

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What All Scientists Do


• Science is the study of the natural world through careful observation and investigation. There are many branches of science.

• Scientists use investigations to try to explain how and why things in the natural world happen.

• Investigations are procedures carried out to observe, study, or test something.


What All Scientists Do


• All scientists observe by using their five senses to collect information.

• All scientists compare by finding ways objects and events are similar and different.

• Scientists must think critically about the results of their investigations to learn more about the natural world.


Prove It!


• Scientists collect evidence, or information, to explain observations during a scientific investigation.

• Evidence can be direct. A fossil of a dinosaur skull is direct evidence that dinosaurs once lived.

• Evidence can be indirect. A fossil of a dinosaur footprint is indirect evidence of dinosaurs.


Prove It!


• Here is an example of a scientist collecting evidence:

• In the 1660s, a scientist named Dr. Francesco Redi designed an experiment on maggots.

• At that time, most people thought maggots grew out of rotting meat.


Prove It!


• Redi put fresh meat in two jars. He covered one jar with cloth and left the other jar uncovered.


Prove It!


• He observed the meat over many days.

• He saw that flies landed on the meat in the uncovered jar. No flies landed on the meat in the covered jar.


Prove It!


• Soon, there were maggots on the meat in the uncovered jar. There were no maggots on the meat in the covered jar.


Prove It!


• Redi repeated the experiment many times.

• Each time, he observed the same thing: Maggots grew on meat that flies landed on, but no maggots appeared on meat with no flies.

• He concluded that maggots come from eggs that flies lay.


Prove It!


• Which jar would the meat in the image below have been in?

A Sticky Trap


How to Draw Conclusions

• Scientists repeat investigations over and over to draw conclusions. The conclusions are always based on evidence.

• A scientist uses inferences to draw conclusions based on evidence.

• Scientists do not use feelings or opinions to draw conclusions.


Opinion or Evidence?

• Opinions are beliefs or judgments. Scientists do not use opinions to draw conclusions.

• Personal feelings and opinions should not affect how you do investigations or your conclusions.

• You should not ignore evidence, even if you do not like what it means.




Knowledge Grows


• Scientists communicate, or share, the results of investigations.

• Other scientists can repeat the investigations and compare the results.

• Scientific knowledge grows as scientists expand on one another’s ideas.


Meet Scientists


• Many people work as many different types of scientists.

• Astronomers: study how the universe works, using time and space relationships to investigate it

• Botanists: investigate questions about plants, such as how environmental conditions impact the plant cycle

• Taxonomists: identify and classify living things into categories based on specific characteristics


Meet Scientists


• Scientists may need to place objects or events in order. They may also need to classify objects or events based on specific characteristics.

• How do you know the order, or correct sequence, for the images below?

Unit 1 lesson 1 What is Science

Education

conclusions scientists

branches of science

different types of scientists

fresh meat

rotting meat

uncovered jar

results of investigations

indirect evidence of