<span>The answer is a certain required chemicals must be actively
transported. Blood brain barrier is a
selective membrane that separates blood circulating from the brain and the
fluid of extracellular in the central nervous system. This is also called a
filtering mechanism, the capillaries that carry blood to the brain and spinal
cord tissue blocking the path way of the certain substance.</span>
Answer:
Sea turtle migration is the long distance movements of sea turtles. It may refer to adults or the offshore migration of hatchlings.
Answer:
He found that the planets do not all move at the same speed. (A)
Explanation:
Acids are solutions/substances that tend to break off to make a hydrogen (H+) ion when placed in an aqueous solution; i.e. solution with water as its solvent.
Bases, on the other hand, produce a hydroxide ion (OH-) when placed in an aqueous solution.
Thus, by definition, we can safely assume that a solution containing a large number of hydroxide ions is considered a base.
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Answer:
sinoatrial node and atrioventricular node
