| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.34 |
| Score | 0% | 67% |
__________ and __________ pair to strengthen bones.
iron, calcium |
|
vitamin D, calcium |
|
vitamin D, magnesium |
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calcium, vitamin A |
Vitamin D helps calcium strengthen bones while also aiding muscle, nerve, and immune system function.
In the heart, blood flows from the __________ ventricle to the lungs then back to the heart via the __________ atrium.
right, left |
|
left, left |
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left, right |
|
right, right |
The two largest veins in the body, the venae cavae, pass blood to the right ventricle which pumps the blood to the lungs through the pulmonary artery. Blood picks up oxygen in the lungs and returns it to the left atrium via the pulmonary vein.
Which of the following describes the Earth's mantle?
makes up most of Earth's volume |
|
dense |
|
hot |
|
all of these |
Mantle makes up 84% of the Earth's volume and has an average thickness of approximately 1,800 miles (2,900 km). It is dense, hot, and primarily solid although in places it behaves more like a viscous fluid as the plates of the upper mantle and crust gradually "float" along its circumference.
In cell biology, the primary difference between anaerobic and aerobic respiration is that aerobic respiration requires:
mitochondria |
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water |
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oxygen |
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sugar |
Some plant cells produce their own energy through photosynthesis which is the process by which sunlight, carbon dioxide, and water react to make sugar and oxygen. Animal cells cannot produce their own energy and, instead, generate energy when mitochondria consume outside sugar and oxygen through aerobic respiration.
The coldest point in the Earth's atmosphere is reached in which atmospheric layer?
stratosphere |
|
thermosphere |
|
mesosphere |
|
troposphere |
In the mesosphere, temperature again drops as altitude increases until the coldest point in the Earth's atmosphere, the mesopause, is reached where temperatures fall to −225 °F (−143 °C).