| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.06 |
| Score | 0% | 61% |
What part of the food chain serves only as food for other organisms?
decomposers |
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producers |
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secondary consumers |
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primary 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
In the water cycle, infiltration is most closely related to:
water table |
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runoff |
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rivers |
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oceans |
The water then accumulates as runoff and eventually returns to bodies of water or is absorbed into the Earth (infiltration) and becomes part of the water table, an underground resevoir of fresh water.
Within DNA, a variety of a particular gene is called a(n):
homozygous |
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chromosome |
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allele |
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heterozygous |
The gene is the base unit of inheritance and is contained within DNA. A gene may come in several varieties (alleles) and there are a pair of alleles for every gene. If the alleles are alike, a person is homozygous for that gene. If the alleles are different, heterozygous.
Arteries carry __________ blood at __________ pressure.
deoxygenated, low |
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oxygenated, low |
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deoxygenated, high |
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oxygenated, high |
Veins carry blood back to the heart from the body. While arteries are thick-walled because they carry oxygenated blood at high pressure, veins are comparatively thin-walled as they carry low-pressure deoxygenated blood. Like the heart, veins contain valves to prevent blood backflow.
The four planets closest to the Sun are called terrestrial. What does terrestrial mean?
the planets have magnetic fields |
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the planets are Earth-like |
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the planets have water |
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the planets have moons |
The four planets closest to the Sun (Mercury, Venus, Earth, and Mars) are called terrestrial (Earth-like) planets because, like the Earth, they're solid with inner metal cores covered by rocky surfaces.