When you get sick, your body springs to action. Your body starts to fight the illness. Thats why you want to eat right and get plenty of sleep. You need a strong immune system to fight off illness. Plants dont have an immune system. That does not mean they do not get sick. Plants are affected by disease just like us. Typically, their first line of defense is the death of part of the plant. This prevents the infection from spreading. Many plants also produce special chemicals to fight disease. For example, willow trees produce a chemical to kill the bacteria. The same compound is used in many acne products. You can see a picture of a willow tree in Figure Plants may be smarter than we think. No, they cannot talk to each other. They may be able to send messages, though.

Question: "What kind of organisms can get sick even though they don't have immune systems?"

Answer: "Plants"

Response: yes

So what is gravity? A typical definition of gravity is that it is a force. It causes an attraction between two masses. According to this definition, anything that has mass exerts a force. Any object exerts gravity on other objects. It does not matter how small it is, it has gravity. The more matter an object has, the more gravity it has. Your pencil has a tiny bit of gravity, but far too little to notice. What about a planet? It would have a lot of gravity. An objects gravity exerts a pull on other objects. Friction only occurs between objects that are touching. Gravity can act between objects that are not touching. In fact, gravity can act over very long distances. Where else can you feel gravity?

Question: "How do objects interact under gravity?"

Answer: "there is friction"

Response: no

Mechanical energy is a combination of the energy of motion or position. This type of energy describes objects that are moving or could move. A moving ball can have energy from motion. An arrow can also have the energy of motion. Both are types of mechanical energy. Can you think of some other examples? Where does the energy of motion come from? It comes from the energy created by position. This energy is stored energy. This means it is not moving yet, but it has the potential to move. How can you store energy? The arrow gains energy from the drawn bow. As the arrow is released, the bow releases its stored energy and puts the arrow into motion. Can you think of some other ways to store energy using position?

Question: "What kind of energy do objects that are moving or could move possess?"

Answer: "Positional"

Response: no

After his cousin Joe dies , Layne Vassimer and his girlfriend Macy , along with their friends Stephen , Maurice , Iris and Katrina , decide to clean up Joe's house with the intention of selling it . When they see it for the first time , they discover the house completely covered in plates of iron armor . The group also finds crop circles in the nearby cornfield . When Iris , one of their friends , suddenly disappears they realize something is really wrong . During a blackout , the house is attacked by aliens , who had previously killed Joe and abducted Iris . The group figures out the aliens are allergic to iron , Joe had covered the house in it to keep them out . They attempt to fight the aliens off , but the house is eventually blown up with Layne , Macy , and Katrina the only survivors . In the end , they drive off , listening to the radio . They hear a news report stating that the blackout they experienced affects five western states and parts of Canada . They also hear that people everywhere are being attacked by '' strange creatures . ''

Question: "Which relative of Joe's discovers that his house is covered in plates of iron armor?"

Answer: "Macy"

Response:
no