Easy
Moderate
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Hard
100

 carbon dioxide:

a molecule made of carbon and oxygen atoms.


100

evidence 

information about the natural world that is used to support or go against (refute) a claim

100

proteins 

a category of large molecules that performs important functions inside living things.

100

system 

a set of interacting parts forming a complex whole.

200

Cellular respiration 

a chemical reaction between oxygen and glucose that releases energy into cells.


200

glucose 

a molecule that organisms can use to release energy, and that is made of carbon, hydrogen, and oxygen atoms.

200

reasoning 

the process of making clear how your evidence support your claim.

300

chemical reaction

a process in which atoms rearrange to form new substances.

300

metabolism 

the body's use of molecules for energy and growth

300

respiratory system 

the body system that takes in oxygen and release carbon dioxide.

400

circulatory system 

the body system that transports molecules to and form all the cells of the body 

400

molecule 

a group of atoms joined together in a particular way.

400

scientific argument

a claim supported by evidence.

500

energy 

the ability to make things move or change.

500

oxygen 

a molecule that organisms get from the air or water around them and use to release energy.

500

starch 

a type of energy storage molecules made of many glucose molecules connected together.