You are observing a single cell under a microscope. You go home for the night, and the next day you see four cells. The four cel
ls look similar, and when you stain them with a dye that binds to DNA they all appear to contain the same amount of DNA as the original cell. What likely happened overnight?
Using its web as a gill, the diving-bell spider can live underwater with only occasional visits to the surface. The arachnid (Argyroneta aquatica) breathes air from a bubble that it grabs from the surface of water using fine hairs on its abdomen.