| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.12 |
| Score | 0% | 62% |
In cell biology, where does DNA replication take place?
nucleus |
|
mitochondria |
|
Golgi apparatus |
|
cytoplasm |
The cell nucleus contains the genetic material of the cell and is where DNA replication takes place.
Veins carry blood __________ the heart.
all of these |
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back to |
|
within |
|
away from |
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.
Which of the following substances gives up positively charged hydrogen ions (H+) when dissolved in water?
alkaline |
|
base |
|
solution |
|
acid |
An acid is a substance that gives up positively charged hydrogen ions (H+) when dissolved in water. A base (alkaline) gives up negatively charged hydroxide ions (OH-) when dissolved in water. pH is a scale that measures of how basic or acidic a solution is. Numbered from 0 to 14, solutions with a pH of 7 are neutral, less than 7 are acidic, more than 7 are alkaline.
Water coming to a boil on a stove, ice melting, and steam from a cup of coffee are all examples of which of the following?
conduction |
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convection |
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reflection |
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radiation |
Convection is the transfer of heat by the circulation or movement of the heated parts of a liquid or gas.
Convert 0C° to F°.
0 |
|
32 |
|
-32 |
|
16 |
To convert from C° to F° use:
\(F° = {9 \over 5}C° + 32\)
\(F° = {9 \over 5}(0) + 32\)
\(F° = 0 + 32 = 32\)