A laboratory rat has an electrode implanted in its brain. By pressing a metal bar in its cage, the animal can activate the electrode. You are analyzing the data from the most recent experiment day and find that the rat pressed the bar over and over again. The rat did not even eat during the experimental period because it was too busy pressing the bar. In which location is the electrode likely to be implanted?

What is the main structural difference between enveloped and nonenveloped viruses? a) enveloped viruses have their genetic material enclosed by a layer made only of protein. b) nonenveloped viruses have only a phospholipid membrane, while enveloped viruses have two membranes, the other one being a protein capsid. c) enveloped viruses have a phospholipid membrane outside their capsid, whereas nonenveloped viruses do not have a phospholipid membrane. d) both types of viruses have a capsid and phospholipid membrane; but in the nonenveloped virus the genetic material is between these two membranes, while in the enveloped virus the genetic material is inside both membranes.