Where do the aurora borealis usually take place at?

magnetic north pole

Explanation:

They occur most frequently in a belt of radius 2500 km centered on the magnetic north pole. This so-called auroral zone extends over northern Scandinavia, Island, the southern tip of Greenland and continuing over northern Canada, Alaska and along the northern coast of Siberia.

protocol for imps extraction focusing on membrane protein extraction, solubilisation, and purification.

lysosome is this part of the cell is surrounded by a very thick outer membrane to protect the rest of the cell from its strong enzymes.