Calcium pump Calcium pump Calcium pumps are a family of ion transporters found in the cell membrane of all animal cells. They are responsible for the active transport of calcium out of the cell for the maintenance of the steep Ca electrochemical gradient across the cell membrane. Calcium pumps play a crucial role in proper cell signalling by keeping the intracellular calcium concentration roughly 10,000 times lower than the extracellular concentration. Failure to do so is one cause of muscle cramps. The plasma membrane Ca ATPase and the sodium-calcium exchanger are together the main regulators of intracellular Ca concentrations. Ca has many
Answering the Question: What is Enlightenment? II of Prussia for creating these preconditions. Kant focused on religious issues, saying that "our rulers" had less interest in telling citizens what to think in regard to artistic and scientific issues. Kant answers the question in the first sentence of the essay: "Enlightenment is man's emergence from his self-incurred immaturity (Unmündigkeit)." He argues that the immaturity is self-inflicted not from a lack of understanding, but from the lack of courage to use one's reason, intellect, and wisdom without the guidance of another. He exclaims that the motto of enlightenment is "Sapere aude"! – Dare to be wise! In the