Grade 7 · Science
Cells, genetics, body systems, and Earth science. Written in American English for students, parents, and teachers in the United States.
Open a card to see the answer. These are original practice items for US elementary students — not a state test copy.
Answer: blood
The heart pumps blood through vessels.
Answer: gas exchange (oxygen and carbon dioxide)
Lungs bring in O₂ and release CO₂.
Answer: breaks food into nutrients
Mouth, stomach, intestines.
Answer: away from the heart
Veins return blood toward the heart.
Answer: nervous system
It sends and receives signals.
Answer: movement
Muscles pull on bones.
Answer: kidney
Kidneys are in the excretory system.
Answer: carbohydrates
Sugars and starches.
Answer: protons and neutrons
Electrons move outside the nucleus.
Answer: protons
It identifies the element.
Answer: atomic number
Periods are rows; groups are columns.
Answer: H₂O
Two hydrogen, one oxygen.
Answer: makes a new substance
Rusting and burning are chemical.
Answer: shiny and good conductors
Copper wires conduct electricity.
Answer: Au
Ag is silver; Au is gold.
Answer: two or more elements chemically bonded
NaCl is a compound.
Pick the next article in this topic — that is how a magazine issue is meant to be used.
