A DNA molecule is a twisted ladder-like stack of building blocks called nucleotides. There are four types of DNA nucleotides-adenine, cytosine, guanine, and thymine-or A, C, G, and T, for short.ou've got six billion of these pairs of nucleotides in each of your cells, and amongst these six billion nucleotide pairs are roughly 23,000 genes.
Where does lightning occur?This map from NASA shows color variations indicating the average annual number of lightning flashes per square kilometer. WhereThe new maps show that Florida, for example, is one place where the rate of strikes is unusually high. This is because Florida experiences two sea breezes: one from the east coast and one from the west coast.
About 90% of all tornadoes worldwide occur in the United States. More than half strike within a couple of hundred miles of Missouri and Arkansas. Tornadoes occur frequently in â¦ Missouri, Arkansas, Kansas, Oklahoma, Texas, Tennessee, and Mississippi.They are a bit less frequent in the northern plains states and Ohio Valley. Nearly every state in the USA has had tornadoes at some time.tornado alley) Why they occur is because: they get warm moist air from the gulf of Mexico that collides with cold â¦ dry air from Canada, and they get contained in this area by the mountain ranges that are on either side, when the air collides they swirl around each other causing a tornado. 2 people found this useful.