| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.48 |
| Score | 0% | 70% |
In the food chain, bacteria and fungi convert the organic matter in the dead bodies of plants and animals into simple nutrients. Bacteria and fungi are:
producers |
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scavengers |
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decomposers |
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primary consumers |
Decomposers (saprotrophs) are organisms such as bacteria and fungi that break down the organic matter in the dead bodies of plants and animals into simple nutrients.
Blood pressure is generally highest in which of the following?
arteries |
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heart |
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veins |
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capillaries |
Arteries are thick-walled because they carry oxygenated blood at high pressure, veins are comparatively thin-walled as they carry low-pressure deoxygenated blood.
Someone who has Rh-factor __________ blood cannot receive blood with a __________ type.
negative, positive |
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positive, antigen |
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positive, negative |
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antigen, negative |
Blood transfer is limited by the type and Rh factor of the blood. Someone who has Rh-factor negative blood cannot receive blood with a positive type but a person with Rh-factor positive type blood can receive Rh-negative blood. Type O negative blood is the universal donor because it can be given to a person with any blood type. Type AB positive is the universal recipient meaning someone with this blood type can receive any other type of blood.
__________ and __________ pair to strengthen bones.
calcium, vitamin A |
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iron, calcium |
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vitamin D, magnesium |
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vitamin D, calcium |
Vitamin D helps calcium strengthen bones while also aiding muscle, nerve, and immune system function.
The rate of vibration of sound is called:
volume |
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period |
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frequency |
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amplitude |
The rate of vibration of sound is called frequency and is measured in hertz (Hz). One hertz is one repetition per second and sounds with high frequency have a higher pitch than sounds with lower frequency. Humans can hear sounds in the range of 20 Hz to 20 kHz.