| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.20 |
| Score | 0% | 64% |
Blood is created in:
bone marrow |
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the heart |
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the liver |
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red blood cells |
Blood is created in bone marrow and is made up of cells suspended in liquid plasma. Red blood cells carry oxygen, white blood cells fight infection, and platelets are cell fragments that allow blood to clot.
Velocity is the rate at which an object changes position. What is the formula for velocity?
\(\vec{v} = { \vec{d} \over t } \) |
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\(\vec{v} = \vec{d}t \) |
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\(\vec{v} = { t \over \vec{d} } \) |
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none of these |
Velocity is the rate at which an object changes position. Rate is measured in time and position is measured in displacement so the formula for velocity becomes \(\vec{v} = { \vec{d} \over t } \)
A major difference between sound waves and light waves is which of the following?
all of these are correct |
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a sound wave cannot travel through a vacuum |
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a sound wave is much slower than a light wave |
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a sound wave is mechanical while a light wave is electromagnetic |
A vibrating object produces a sound wave that travels outwardly from the object through a medium (any liquid or solid matter). The vibration disturbs the particles in the surrounding medium, those particles disturb the particules next to them, and so on, as the sound propagates away from the vibration.
In the heart, the __________ artery and vein manage blood flow to the lungs.
atrial |
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capillary |
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pulmonary |
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aorta |
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.
In the food chain, omnivores may be which of the following?
primary or tertiary consumers |
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primary or secondary consumers |
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secondary consumers or scavengers |
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secondary or tertiary consumers |
Secondary or tertiary consumers may be omnivores.