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The heart plays important roles in supplying oxygen and removing toxic waste to/from our body. In basic concepts, the heart is made up of 4 chambers, two on the top and two at the bottom, the top are know...
The human heart is described as a double pump because blood passes through it and gets pumped out of it twice in a single circuit of the circulatory system. A normal heart is separated into two halves, ri...
A synapse is a junction between a neurone and the next cell. When an action potential arrives at the presynaptic membrane, voltage-gated calcium ion channels open. Calcium ions (Ca2+) diffuse into the syn...
It controls what enters and leaves the cell.
Synapses are the junctions between neurons. An electrical impulse travels down the first neuron and arrives at the presynaptic membrane. The presence of an electrical impulse causes chemicals called neuro...
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