Exploratorium Field Trip Pathways

Traits of Life: What Does It Mean to Be Alive?

The following California State Science Standards are relevant to this Pathway:

Grade Topic Subsection
4 Life Sciences 2. a, b, c; 3. a

Investigation and Experimentation

6. a
5 Life Sciences 2. a, b, e, f, g
Investigation and Experimentation 6. a, f, h
6 Ecology 5. a
Heat 3. b
Investigation and Experimentation 7. a, h

California State Standards

This Pathway is designed to help students explore the concepts of life by observing, asking questions, and making connections.

This Pathway uses questions to introduce students to fundamental concepts of life. These questions are open-ended, for the most part, and are meant to make students think and ask more questions. The classroom may be a good space to engage students in discussion, both before and after their visit to the museum, and to have them begin designing experiments to answer testable questions. Students may refer back to their notes from the Exploratorium to guide them in further learning about the Traits of Life.

Before Your Visit
Have students take time to write or discuss the following question in small groups:

How do you know that you are alive? List some examples of things that you can observe about yourself or others.

The motivation behind this question is to have students begin exploring a very complex question by making simple observations.

During Your Visit

Please plan for unstructured time during your field trip. Leaving about half of your total field trip visit unstructured allows students to follow their own interests while exploring the museum.

1. Groups of 2 or 3 work well for this Pathway.
2. Have students visit the exhibits named in green boxes.
3. Students should answer the questions.
4. Students should also write down any questions they have!

Can't find an exhibit or have a question? Ask an Explainer.


Sometimes it's easy to tell that something is alive but hard to explain why. Sometimes it's not easy to decide whether or not something is alive. We can start by making observations. If you come up with any questions, write them down.

At some point, go to the Cheek Cell Demonstration.

Draw and/or describe what you see.

Drawings/Answers will vary. Students should be able to see a cell membrane and nucleus for each cell.





In your own words, explain: What is a cell? From what you know, who/what has cells?






Classroom Discussion: Now that you have seen cells in your cheeks, where else do you think you might have cells? If you look at any part of yourself under the microscope, you’ll see cells—our bodies are made entirely of cells. Can you think of any living things that might not be made of cells? How can you test to find out? Can you think of anything else that all living things have in common?

Look at the goldfish.

Are They Alive? What Are Your Clues?





Students’ observations may include things such as breathing, eating, and movement. It’s easy to tell that the goldfish are alive because they have relatively similar behaviors to humans.

Look at the Chick Embryos Exhibit.

Draw and/or describe what you see in one of the dishes.

What Is It Made Of?
(Read the exhibit label for a hint.)


Things You Find Is It Alive? What Are Your Clues?
    Answers will vary. Some students may point out that the hearts are beating, indicating that the embryos are alive. Some students may point out that the embryos are dying because they’re no longer protected by their shells.

Now go look at the Living Color exhibit.

Billions of years ago, bacteria emerged as one of the very first living things on earth.

Can you see anything about the bacteria that is similar to other living things that you know about (such as the goldfish, plants, etc.)?



It’s difficult to know that the bacteria are alive by looking at them with the naked eye alone. Some students may point out that the colors of the bacteria are evidence of the use of energy (like plants). Some students may have some previous knowledge of bacteria, including that they reproduce.

Classroom Discussion: Is there any one way to categorize living and nonliving things? For example, are all things with color alive? Are all things that move alive? Is there anything about the organisms you have looked at so far that they all have in common (i.e., they’re made of cells)? How do our past experiences help us understand what is alive?

Look at the Energy From Death exhibit.

Take a close look at what is going on inside the box. Make a list of 5 things you find.

Things You Find Is It Alive? What Are Your Clues?


1. Choose something interesting in the box and draw it.

Write down what you think it is and why you chose to draw it so that you’ll remember it later.



The box contains dead animals, living beetles that are eating the dead animals, and inanimate objects such as the beetle nesting material and the tank itself.

2. What do you think is happening to the things in this box?

Classroom Discussion: What is the line between life and death? Is something that is dead different from something that was never alive? Can energy and nutrients for living things still be extracted from things that are dead?


Energy itself is difficult to see, but we can observe signs of organisms using energy.

Look at the Oxygen Bubbles exhibit.

Draw what you see.   Plants use energy from light to make their food in a process called photosynthesis.

In the equation below, circle the parts of photosynthesis that you can see in the exhibit.
(Hint: Circle 3 things.)

Living plants use:

To make:

In this exhibit, students can see water, light, and oxygen bubbles (coming off of the leaves).

Classroom Discussion: Plants are the connection between living things and the sun’s energy because they are able to photosynthesize (to make with light). Energy flows through food webs from producers to consumers.

Put on a glove at the Hot Pile exhibit and reach into the pile.

1. Does it feel warmer or cooler than the air in the room? __________

2. Look at the thermometer—how hot is it in there? __________

Heat is a sign of energy use. Bacteria in the pile are breaking down the organic material in the pile for food, giving off heat as they use energy.

The hot pile is usually 100 to 130 degrees Fahrenheit, much warmer than room temperature.

3. When you exercise (run around, jump up and down, etc.) do you usually feel warmer or cooler? __________

Classroom Discussion: What is the connection between the heat in the pile and the heat we produce when we use energy? Have students do jumping jacks for one minute and talk about whether they feel their bodies getting warmer. When living things use energy, heat is given off as a byproduct.

Choose one exhibit that shows organisms using energy.

Exhibit Name Describe the Exhibit Clues of Energy Use





Classroom Discussion: Are all things that use energy alive? Can something be alive if it never uses energy?

After Your Visit
Allow students time to write or discuss the following questions in small groups. You may also choose to address the Classroom Discussion questions listed in the Pathway.

1. What does it mean to be alive?
2. What do you have in common with the living things you saw in the Traits of Life exhibition at the Exploratorium?
3. Did the Traits of Life exhibition help you understand what it means to be alive or did it leave you with more questions?

Make a class list of questions that were generated by looking at the exhibits and following the Pathway. These questions can be used to further students’ explorations by having them write essays or design experiments, or by initiating observations of living and nonliving things.