A relation of a substance's mass to its volume.
Density = Mass / Volume
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Answer:
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Explanation:
Blood vessels are vessels that carry blood through organs and tissues. The five types of blood vessels are: arteries, veins, arterioles, capillaries, and venules. The main function of blood vessels is to carry blood throughout the body.
If a human doesn't have factor 8 , <span>hemophilia
will happen (it is the most usual form of </span><span>hemophilia )</span>
Both fission and fusion<span> are nuclear reactions that produce energy, but the applications are not the same.</span>Fission<span> is the splitting of a heavy, unstable nucleus into two lighter nuclei, and </span>fusion<span> is the </span>process <span>where two light nuclei combine together releasing vast amounts of energy.</span>
Answer:
C. tetanic contractions might occur, which would stop the heart's pumping action.
Explanation:
The absolute refractory period of the cardiac muscle action potential refers to the time interval when the voltage gated sodium channels are inactivated. The absolute refractory period lasts ~180 msec. The action potential lasts 200-220 msec.
The refractory period of cardiac muscle is dramatically longer than that of skeletal muscle. This prevents tetanus from occurring and ensures that each contraction is followed by enough time to allow the heart chamber to refill with blood before the next contraction.
In order words, It is important for the cardiac muscle cells to have a longer refractory period, because if they were short like the skeletal muscles, the heart could enter tetanic contraction/summation which is when muscle is stimulated so rapidly that it does not have a chance to relax at all between stimuli.