1.The presence of valves 2.the milking action of skeletal muscles 3. the veins as the muscles contract
It’s halved and it doesn’t depend on the species
Very simple. At rest, you have a number of bpm. After exercise, the heart can't return abruptly to the rest speed, and it keeps a faster rate for a while.
Differentiation is the process that involves the turning off or on the genetic information of a cell.
Differentiation is the process in which a young and immature cell changes into a specialized cell (a mature form with distinct function). Generic embryonic cells undergo differentiation to become specialized cells through the process of gene expression in which specific combination of genetic instructions are turned on (expressed) or off (repressed).
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