The "strings" in a stalk of celery are made up of xylem and phloem. Which part of your body comes closest to serving the same function?

1. Skeleton

   No. Your skeleton provides support and protection. In plants, the cell wall provides support and protection.

2. Intestines

   No. Your intestines allow you to absorb nutrients from your food. Plants make their own food, so they do not need a digestive system.

3. Nerves

   No. Your nerves carry signals to let the parts of your body communicate. They carry messages for your senses, to move your muscles, etc. Instead of having nerves, plants release chemicals that signal other parts of the plant.

4. Blood Vessels

   Yes! Your blood vessels carry water and nutrients to different parts of your body. In plants, the xylem is made up of tubes that carry water and some nutrients from the roots upwards to other parts of the plant. The phloem is made up of tubes that carry the sugar produce by photosynthesis to other parts of the plant. While they work in very different ways, your blood vessels serve basically the same function (carrying water and nutrients) as the xylem and phloem in plants.

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This is Johnson Wash, that runs down the middle of the canyon where we live. It is usually dry, but when it rains up north, we get flash floods. Is this an example of erosion, weathering, both, or neither?

1. Erosion

   Yes, the is partially correct! You can tell by the muddy appearance of the water that it is carrying sand, clay and dirt along with it. Erosion is when bits of rock are moved by wind, water, ice, or gravity, so this counts as erosion..

2. Weathering

   Yes, the is partially correct! The term "weathering" causes confusion because it sounds like it has something to do with weather. In Earth Science, weathering means "breaking apart." Weathering breaks rocks apart into smaller bits. The fast moving water causes smaller rocks to smash into larger rocks, breaking them apart.

3. Both erosion and weathering

   Yes! The flash flood in this photo is causing weathering, and erosion. As the flood decreases, and the water slows down, it will drop the sand, clay, dirt, and rocks in a process called deposition.

4. Neither erosion nor weathering

   No. This flash flood is causing both weathering and erosion.

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