Answer: A: Its fertile oases enabled farmers to grow enough food for themselves and for sale.
Explanation: The Arabia region is a region located within the Arabian desert. A desert is an area of extreme heat, often dry weather condition with barren lands that cannot support agriculture and food production. An oases on the other hand is a region of luscious, cultivate-able land within a desert.
Food is one of the most important basic needs of man and hardly can anyone survive without food for more than twenty days. Hence, the presence of oases within the otherwise dry environment of the Arabia region is a major protection against death from hunger.
Taking a closer look at other options, none of them guarantees food supply and income to the Arabia region unlike food production in oases. Hence, the fertile oases is really the most important factor that serves as protection in the region's history.
Correct option: A
Answer: Here you go!
Explanation:
Analogous structures are structures that are similar in unrelated organisms. The structures are similar because they evolved to do the same job, not because they were inherited from a common ancestor. For example, the wings of bats and birds, shown in Figure below, look similar on the outside
Answer:
d. None of these
Explanation:
Probably the identical sequence found in both species<em> </em>is an<em> ultraconserved sequence. </em>
An <u>ultraconserved element</u> is a particular DNI sequence that remains exactly the same through evolution, with almost no modification, and that is shared by at least two completely different species.
These ultraconserved DNI portions seem to be highly essential for life. However, their function could not be determined yet. Most of them do not codify for proteins, but they could play a significant role in gene regulation.
It is suggested that these sequences are so significant for life that only a small change would compromise the organism´s aptitude.