1. `
Structures
Cycles
Processes
Systems

2. Cycles Unicycle Bicycle Tricycle
The word “cycle” is found in many familiar words.
Unicycle
Bicycle
Tricycle

3. Unicycle - uni (one)
Bicycle – bi (two)
Tricycle - tri (three)
Since the prefix of each word refers to a number, what do you think the word “cycle” refers to in the above words?

4. That’s Right! The word cycle refers to the wheel.
A unicycle has one wheel
A bicycle has two wheels
A tricycle has three wheels

5. We use the word cycle to refer to the motion of going around and around.
In Science – events are repeated over and over in a particular sequence or order.
Seasons represent a cycle – spring, summer fall, winter . . .
Can you tell where it begins and where it ends?

6. Where does a cycle end? That’s right!
It doesn’t.
Cycles are continuous.
The motion we observe on a bike represents the motion in several important cycles in our universe. These cycles never end.
Here are some of our most important cycles.

7. Important Cycles
Water Cycle
Carbon Dioxide - Oxygen Cycle

8. Water Cycle Condensation Evaporation Precipitation
Collection or accumulation

9. Does this cycle ever end?
Water Cycle
Evaporation – liquid changes into a gas (water vapor)
Condensation – the water vapor cools and turns back into a liquid (water droplets)
Precipitation – as the droplets increase in size, gravity causes them to fall back to the earth
Does this cycle ever end?

10. Carbon Dioxide - Oxygen Cycle
Plants on land and in water release oxygen, which we and other animals breathe in. We and other animals breathe out carbon dioxide, which is used by plants in the process of photosynthesis.
Will this cycle ever end?
oxygen
Carbon
dioxide
oxygen
Carbon
dioxide
Carbon dioxide
oxygen

11. Processes are taking place!
Within each of these cycles, processes are taking place.
Processes in a cycle are like the verbs in a sentence. They denote ACTION.
For example, in the water cycle the processes (actions) taking place are evaporation, condensation, precipitation and collection/accumulation.

12. Processes are Actions Evaporation: liquid changes into a gas.
Condensation: gas (water vapor) changes into a liquid.
Precipitation: rain, snow, sleet or hail falls to earth due to gravity. Fog forms.
Notice how processes involve ACTION words (verbs).

13. Find the Processes
What do you think are the ACTION words in the Carbon Dioxide - Oxygen Cycle?
Plants on land and in water release oxygen, which we and other animals breathe in. We and other animals breathe out carbon-dioxide, which is used by plants in the process of photosynthesis

14. Did you find the action words?
Release oxygen
Breathe In
Breathe Out
Photosynthesize

15. Now you know . . . . that cycles have processes
New Information: Cycles also have STRUCTURES
Structures in a cycle are like the nouns (OBJECTS) in a sentence. The objects are arranged in a particular way so that they “work” correctly.
For example, look at the structures in the Water Cycle.

16. What are the structures you see?
Condensation
Evaporation
Precipitation
Collection or accumulation

17. Structures (Objects) in the Water Cycle
Ocean, lakes, rivers
Water vapor
Sun
Clouds
Water droplets (rain)
Notice how structures are noun words or objects.

18. Find the structures in the Carbon Dioxide - Oxygen Cycle
Remember to name the objects you see
oxygen
Plants on land and in water release oxygen, which we and other animals breathe in. We and other animals breathe out carbon dioxide which is used by plants in the process of photosynthesis.
Carbon
dioxide
oxygen
Carbon
dioxide
Carbon dioxide
oxygen

19. Structures (Objects) in the Carbon Dioxide - Oxygen Cycle
Plants
Bird (animal)
People
Underwater Plants
Fish (marine animals)
Notice how structures are noun words or objects.
The STRUCTURE of an object is the way the object is designed or arranged so that it does the job it is meant to do. For instance, people have lungs that take in the oxygen. The lungs are arranged especially to breathe in and out.

20. REVIEW There are many cycles in our world.
Can you name two very important cycles?
Water Cycle
Carbon Dioxide - Oxygen Cycle

21. All Cycles have processes and structures, which interact.
How would you define processes in a cycle?
Processes are the ACTIONS taking place
How would you define structures in a cycle?
Structures are the OBJECTS in a cycle. They are designed or arranged in a way that allows them to do the work they do.
All Cycles have processes and structures, which interact.
Processes
Structures
Structures
Processes

22. What can be bigger than a Cycle?
System

23. A System is made up of Solar System Cycles Processes Structures
Cycles, processes, and structures are connected to other cycles, structures, and processes to make up an entire system.
One of the biggest systems
fifth graders learn about is our
Solar System

24. Some of the structures in our Solar System include:
Some of the Processes of our Solar System include:
Revolution of the planets around the sun
Rotation of earth
Revolution of the moon around earth
Movement of comets, asteroids and meteors in space
Some of the structures in our Solar System include:
Sun
Nine Planets (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto)
Asteroids
Meteors
Comets

25. On a separate sheet of paper, try to draw the Solar System with the structures listed. How might you show the processes taking place?

26. Other important systems on Earth
Ecosystems include cycles, processes, and structures that interact in order for the survival of species.
The two cycles (water and carbon dioxide - oxygen) are all parts of an ecosystem.
Sometimes we define different ecosystems, such as a desert ecosystem or a rainforest ecosystem.

27. Can you identify the cycles, processes. and structures in this
Can you identify the cycles, processes and structures in this desert ecosystem?
Do you think that all of the cycles, processes and structures for a desert ecosystem are drawn in this diagram? Why or why not?

28. Two examples of smaller systems are simple and parallel circuits
A system can be as large as the Solar System or as simple as a circuit.
The simple circuit above has cycles (energy flow), processes (transfer of energy) and structures (battery, wiring, light bulb, switch).
The parallel circuit below also has cycles, processes, and structures.

29. What about systems in our body?
Many systems are located in your very own body!
Can you name some systems?
Digestive System
Respiratory System
These are only two But there are many more!

30. Systems can involve organisms such as an ecosystem or a system in our bodies. (Life Science)
Systems can involve earth and space objects such as the Solar System. (Earth Science)
Systems can also involve machines. (Physical Science)

31. The most important fact to remember about SYSTEMS is:
Systems are made up of
cycles
processes
and structures
that interact in order for the system to work.
Discuss with your teacher and classmates what you think would happen if one of the parts of a system were removed. Example: What would happen if the sun were removed from the water cycle?