one reason for the decline inthe population of marine iguqnes is that invasive speciesnare preying upon themvand there eggs hope this helps
I believe the biggest space mission of the twenty-first century will be a manned mission to Mars, and the colonization that follows. This is the stated goal of several nations, companies, and individuals, all with considerably deep pockets. This mission will not only be a huge leap forward in space exploration, it will usher in a new era in human history in which the human race is an interplanetary civilization, a natural milestone as humanity continues to progress and advance.
Significant challenges are many and overwhelming. In terms of getting to mars, we need efficient, powerful propulsion systems and a spaceship that can not only accommodate a full crew for a mission that would likely last years, but withstand the various hazards that a long trip through space and entrance into the Martian atmosphere will entail. In terms of colonization, significant challenges will include establishing efficient and frequent travel/transport between the planets, and in the longer term, the necessity to terraform the planet (make it more like Earth) so that humans can more easily live there.
Answer:
DNA is double-stranded, while RNA is single-stranded. RNA contains ribose as a sugar, while DNA contains deoxyribose. Also, three of the nitrogenous bases are the same in the two types (adenine, cytosine, and guanine), but DNA contains thymine while RNA contains uracil.
The role of the nucleolus is to make the monomer of of ribosomes, and ribosomes are used in mRNA to make protein. Therefore the nucleolus plays a major role in the process of making proteins for our body. <span />