7th Science Review

5. The layer of gases surrounding the Earth
6. The control center of the cell that contains DNA is the ______.
11. Organs that filter waste from the blood and produce urine are the ______.
12. A mostly single-celled organism that is not a plant, animal, or fungus is called a ______.
13. What is the height above sea level?
15. The “powerhouse of the cell” that produces energy is the ______.
17. How fast an object moves is its ______.
18. The genetic makeup of an organism is its ______.
20. system The body system that sends signals between the brain and body is the ______.
22. Which type of trait masks another trait when present?

1. Simple machines made of a bar that pivots on a fulcrum are ______.
2. The force that attracts or repels objects made of certain metals is ______.
3. When warm air rises and cool air sinks, this process is known as ______.
4. forces What type of forces result in no change in an object’s motion?
7. What force keeps planets in orbit and objects on the ground?
8. Where does digestion begin after food leaves the esophagus?
9. What part of the water cycle happens when the Sun heats water into gas?
10. force The overall force acting on an object after all forces are combined is called ______.
14. The hottest layer of the Earth's atmosphere is ________.
16. A version of a gene is known as an ______.
19. What is the contamination of air, water, or land?
21. What do we call water that does not soak into the ground after precipitation?