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1. Explain the process that DNA replicates by. Why is it so important that it is carried out in this matter? In explaining the actual process, refer to the possible choices that the scientist considered: conservative, semi-conservative and dispersive.

2. Speciation is a concept that mean one species becoming 2 or more by a progression of different factors (that are key to the theory behind evolution that Darwin proposed) Some biologists classift dogs, wolves, and coyotes as the same species (Canis familiaris). Other seperate coyotes from these group, even though dogs and coyotes can breed in captivity. For what reason would either idean more accepted?

3. Give and describe three categories of evidence that are primarily used in support of Darwin's evolutionary theories.

4. Define symbiosis. Give three types and give 2 examples of each, explaining with each one how the situation applies the example that you give me

5. Name at least 2 major and 2 minor effects that human development and industrialization have had on ecosystems and explain the impact that each has had on both the environment and life in them.

Solution Preview

1. DNA forms a double helix defined by its base pairs Adenine coupled to Thymine and Cytosine coupled to Guanine. These base pairs hold the helixes togeter and also form the genetic code. This means that when DNA replicates its double helix splits up into 2 helixes. By attracting and recoupling to free bases according to the scheme above each helix forms a new double helix identical to the original one. The whole process can to some extent be compared to the zipping and unzipping of a pair of jeans. The base pairs fit together as if they had been zipped into place. Yet the process forms 2 identical double helixes out of one and they are also identical to the original one (unless a mutation occurs somewhere in the structure). The importance of the process is based on the fact that it gives you a very high security in faithfully duplicating the genetic code present in the structure. There can be mishaps though and those form the basis of mutations. I am not familiar with the 3 mentioned historical alternatives to the real process, but now when you do know how it really works and having your textbook on the subject I hope you can construct that part on your own.
2. The normal definition ...