The flu is a virus that attacks your immune system when you are sick. While the flu virus is attacking however you start to get the regular symptoms of getting sick such as a feaver, coughing, vomiting and other things. But the reason why those things happen is because that is the reaction your body is giving off while your immune system is fighting off the virus. Which is why those symptoms stop when you get better.
A DNA molecule is like a ladder because there are two sides (the sugar-phosphate backbones of the two strands) and rungs (each rung being a pair of complementary bases). Twisted, because the molecule is twined in a coil called a helix - or rather, a double helix because there are two strands.
1 hour I think.. correct me if im wrong <3
So by looking at the seismic waves from earthquakes the scientist learned about the crust and the mantle but they also learned about the outer and inner core. To do this you have to look at a different kind of waves, the S (secondary waves) waves that also get released by an earthquake.
