Answer:
What are so called breast-cancer genes, are mutations in two genes: BRCA1 (BReast CAncer gene one) and BRCA2 (BReast CAncer gene two), and are also associated with ovaric cancer. According to the question, these genes are present in the popolation despite surgeries and deaths, and asks why. Surgeries does not eliminate the genes, they eliminate the tumors, and people can still reproduce after that. And also, most people already had offspring before they know they have cancer, so they are inheriting the mutations on the genes anyway.
Explanation:
When a cell undergoes meiosis,the outcome of the process is FOUR HAPLOID CELLS.
Meiosis refers to a form of cell division which always results in the formation of four daughter cells. The four daughters cells produce have diploid cells which contains half the original of chromosomes from the parents. A diploid cell has two of each chromosome, one from each parent. The eggs and the sperms that are involved in reproduction possess haploid cells. In meiosis, the whole process start with diploid cells which divide twice to produce four haploid cells.
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A shield vol may be produced by hot spots which lay far away from the edges of tectonic plates. Shields also occur along the mid-oceanic ridge, where sea-floor spreading is in progress and along subduction related volcanic arcs.
Answer:
Greenhouse Effect
Explanation:
This is called Greenhouse Effect because it is the same concept applied on Greenhouses to grow plants in any time of the year.
Short fall of rain, less fertility of soil, seeds are not well gemernated
(forgot how to spell xD)
Hope this helps!
~ Kana ^^
