Answer:
Perhaps the most amazing thing about mitosis is its precision, a feature that has intrigued biologists since Walther Flemming first described chromosomes in the late 1800s (Paweletz, 2001). Although Flemming was able to correctly deduce the sequence of events in mitosis, this sequence could not be experimentally verified for several decades, until advances in light microscopy made it possible to observe chromosome movements in living cells. Researchers now know that mitosis is a highly regulated process involving hundreds of different cellular proteins. The dynamic nature of mitosis is best appreciated when this process is viewed in living cells.
Explanation:
Around the age of six or seven years, our teeth start to loosen, eventually falling right out. These are what we call milk teeth. Their termination is not a cause for alarm, but rather, a natural process. Soon new teeth replace the ones that are lost. In fact, the deciduous teeth help the permanent teeth erupt in their normal position. Certain of the lower vertebrates, such as sharks and mud puppies, continuously produce new teeth. But most mammals have only two sets. It seems that as you go up on evolutionary scale, there is loss in capacity to replace teeth, scientists say. On the other hand, the teeth become more specialized. For example, in lower organisms, teeth are designed primarily for grabbing and slashing, while in higher animals, they are also adapted for chewing and grinding.
It has been known that in humans the first set of teeth do more than just allow a child to chew. They play a role in stimulating and guiding the growth and development of jawbones and permanent teeth. One of the biggest fallacies is the belief that because deciduous teeth are temporary, they are not important. If a child loses milk teeth prematurely, by accident or because of decay, his jaw and permanent teeth are likely to develop improperly. Prolonged treatment may be needed to set them right.
Another reason for our two sets of teeth is that there is not enough room in a child’s small mouth for the full set of permanent teeth – there are only 20 deciduous teeth, compared with 28 or 32 permanent teeth present in adults.
Hope this helps
Hello there.
<span>The crossing over is a process where the chromatids pair and exchange sections of DNA, which lead to exchange genes (this result is call genetic recombination). So, the crossing over between nonsister chromatids during meiosis is significant in heredity because it leads to an increase of genetic variation (answer d.)</span>
False because they wouldnt be there if they had no function
You can classify them in what phase they are in: solid, liquid, gas
You can classify them in Sizes
You can classify them by the number of moons they have
You can classify them by distance from the sun
You can classify them all as heliocentric or orbiting/circling around the sun
You can classify them by color