Lunar maria (plural form of the Latin word mare, which means sea) are dark surfaces that can be found all over the moon (17% of the Moon is covered in them) that have been created as a result of volcanic eruptions. These areas are made up of basalt, and given that they seemed almost waterlike, the astronomers in the distant past mistook them for seas, whence their name comes.
When it comes to craters, their origin is quite similar - volcanic eruptions created them. When lava starts erupting from a volcano, it has to get out from somewhere - and thus craters are created. If you are referring to lunar craters, however, there are many speculations as to how they were created: due to volcanic eruptions, meteoric impact, or glacier activity.
Hmmm let me think.........
Gravitational push<span>, like a gigantic landslide away from the </span>ridge<span> crest toward the subduction zone (the lithosphere slides on the asthensosphere) </span>Slab pull<span>: results when the lithospheric plate moves farther from the </span>ridge<span> and cools, gradually becoming denser than the asthenosphere beneath it
Hope this helps. :)</span>
Answer:
The correct answer is option 3, that is, blastomeres.
Explanation:
A kind of cell formed by cleavage of the zygote post-fertilization is called a blastomere, it is an important constituent of blastula formation. The formation of blastomere starts instantaneously post-fertilization and is carried through the initial week of the development of embryo. The division of zygote after fertilization is regarded as the first mitotic outcome of the fertilized oocyte. These mitotic divisions take place spontaneously and lead to a grouping of cells known as blastomeres.