conecting concepts

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When you read or listen to science-based information, you will encounter basic scientific concepts that describe and explain the natural world. Concepts are ideas about what things are or how they work. As you will see from the video below, understanding scientific information can sometimes be a matter of life and death.

Watch this video about one of the dangers of scuba diving. Listen carefully for any scientific concepts that are discussed, and think about how they are related to each other. When the video ends, read the questions in the yellow box below. Click the option that correctly answers each question. Click the Next button to move to the next question.

What do blood and gas have to do with each other? How are these concepts related?

Blood is actually a type of gas that takes liquid form when it's inside our bodies.

Blood contains elements that can take the form of gasses, such as oxygen and nitrogen.

Blood acts like a gas as it moves through the bodies of mammals and reptiles.

2 is Right. The concept of gas and gas expansion are needed to talk about how the blood carries oxygen throughout the body.

In this video, how is the concept of gas expansion related to the concept of air pressure?

When gasses are forced inside a small air tank and not allowed to expand, pressure is created.

The pressure inside an air tank destroys some of the gas so that the air can take up less space.

1 is correct Yes, a gas wants to expand, but inside a small tank it cannot, so the gas presses against the sides of the tank.

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How are gasses in our blood like gasses in an air tank?

Gasses in our bodies have the same pressure as gasses in an air tank.

The body is a container, so gasses in the blood are under pressure like the gas in an air tank.

Both blood and an air tank contain a liquid that can become a gas.

2 is correct Yes, both the body (the bloodstream) and an air tank are containers that hold gasses.

Question

How many questions did you answer correctly? Are you ready to start scuba diving?

3: Great! Grab your gear and head to the coast.

2: You'd better read some more about decompression sickness.

1: Scuba diving could be really dangerous for you right now.

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What do you need to do when you read scientific information? To follow a science writer's line of thinking, you have to see the relationships between the concepts that are examined. That is, you have to see how the concepts are connected to each other. Think of concepts as the building blocks of scientific information.

What do related concepts look like? See if you can think of two concepts related to each topic in this slideshow. Try to imagine what questions a scientific article might answer about the two concepts. First, think of your own concepts and questions. Then, click the Show Me button on each slide to compare your ideas to the ones given. Click the arrow to move to the next slide.

What concepts are included in this topic? How are the concepts related?

Butterflies

Concepts: flight and insect bodies

How the concepts relate: What is needed for flight to happen, and how are insect bodies built to meet these requirements?

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Baking

Concepts: heat and chemical reactions

How the concepts relate: How does heat affect the chemicals inside bread ingredients during baking?

BMX Bike Stunts

Concepts: gravity and acceleration (speed)

How the concepts relate: How does speed help resist gravity so that a bike can hover in the air?

Electric Cars

Concepts: electricity and motion

How the concepts relate: How does electricity make a car move?

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Dinosaurs

Concepts: fossils and predators vs. prey

How the concepts relate: What can fossils tell us about how dinosaurs lived?

When you read scientific articles, you may have to figure out how two concepts are related. That's because the relationship between concepts may not be directly stated. It may be suggested, and the writer may expect you to infer the connection. Do you remember what inferences are? Inferences are guesses that are based on given evidence.

Click the Read Me button to read an article that describes how scientists first learned about decompression sickness (DCS). When you are finished reading, answer the questions below. Click the options that correctly answer the questions. Click the Next button to move to the next question.

According to the scientist who figured out how to avoid decompression sickness, how are time and pressure related?

Time and pressure can be used to prevent gas bubbles from forming deep under water.

The more time you take to release pressure on a liquid, the fewer gas bubbles form inside the liquid.

The faster you create pressure on a liquid, the slower the gasses in the liquid can move around.

2 is Right. Bert figured out that bridge builders were moving from high pressure to low pressure much too quickly.

What does bridge building have to do with scuba diving?

Both activities involve placing people deep under water, where the pressure on objects is higher than at the surface.

Both activities require people to wear wet suits and carry oxygen tanks in order to survive.

Both activities can be done without training if someone can hold his or her breath long enough.

1 is correct Yes, diving and bridge building can lead to decompression sickness when people go deep under water.

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How are Robert Boyle's experiments related to the sickness experienced by bridge builders many years later?

Robert Boyle performed experiments on bridge builders as well as on snakes in bell jars.

Robert Boyle used to be a bridge builder before he became a scientist.

What happened in the snake's eye also happened in the bridge builders' bloodstreams.

3 is correct Yes! The same concept applies to both a snake's eye under pressure and bridge builders' blood under pressure. There is liquid in both an eye and in blood, and bubbles of air can form in each under pressure.

The first step in reading scientific articles is to understand the relationship between the concepts that are presented. Sometimes you will need to explain these relationships as well. For example, when you take a science test or write a research report about a science topic, you will have to explain how concepts are related.

To practice this important skill, read the article about the science of scuba diving. It describes exactly what happens to a diver's blood when he or she comes up from the ocean floor too quickly. When you are finished reading, you will complete a worksheet.