| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.62 |
| Score | 0% | 72% |
The process of diffusion allows __________ to exchange oxygen, carbon dioxide, nutrients, and waste between blood and the body's cells.
red blood cells |
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arteries |
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veins |
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capillaries |
Capillaries are small thin-walled vessels that permit the exchange of oxygen, carbon dioxide, nutrients, and waste between blood and the body's cells. This process of exchange is called diffusion.
What part of the food chain serves only as food for other organisms?
decomposers |
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primary consumers |
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producers |
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secondary consumers |
Producers (autotrophs) serve as a food source for other organisms. Typical producers are plants that can make their own food through photosynthesis and certain bacteria that are capable of converting inorganic substances into food through chemosynthesis
__________ is caused by a lack of iron in the diet.
anemia |
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scurvy |
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shingles |
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diabetes |
Anemia, which may cause weakness, dizziness, and headaches is caused by a lack of iron in the diet.
Which of the following is not true of light waves?
are mechanical waves |
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travel faster than sound waves |
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can travel through a vacuum |
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are electromagnetic waves |
Unlike mechanical sound waves that require a physical medium for propagation, light waves are electromagnetic and can travel through empty space. Light waves are also much faster, travelling at 186,000 m/s vs. 343 m/s for sound waves.
An element in the physical state of __________ maintains a constant volume and shape.
solid |
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gas |
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liquid |
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gel |
An element in a solid state has atoms or molecules that are constricted and do not move freely. Solids maintain a constant volume and shape and exist at a lower temperature than liquids or gases.