The evolution of sexual reproduction is a great puzzle in modern evolutionary biology. Many groups of eukaryotic organisms, especially most animals and plants, reproduce sexually. The evolution of sex between two organisms of the same species contains two related but different themes: its origin and its maintenance. However, since hypotheses for the origin of sex are difficult to test experimentally, most of the current work has focused on the maintenance of sexual reproduction. Biologists, including W. D. Hamilton, Alexei Kondrashov, and George C. Williams, have proposed various explanations for how sexual reproduction is maintained in a large set of different living things.
We require to keep our water supply clean because we imbibe that water. If our water supply wasn't unsullied, we would die of dehydration. Another reason is that without water, all the crops would die and we wouldn't have any aliment to victual and so we would withal die of hunger.
Answer: B. False
Explanation:
“Hox” genes are a highly conserved group of genes, all of whose products are transcription factors bearing a specific domain (called a ”homeodomain”). The transcriptional activity of a large amount of genes relevant to embryonic development is controlled by regulatory sites which are able to bind to this domain. Changes in the transcriptional activity of even a single Hox gene may thus have dramatic downstream effects on the phenotype, as this will result in several further genes having their transcription either enhanced or suppressed.
The two main types of fermentation are alcoholic fermentation and lactic acid fermentation. In an alcoholic fermentation, the main product of this process is ethyl alcohol. Lactic acid on the other hand has lactic acid as its main product. When muscle cells run out of oxygen, lactic acid fermentation would commonly take place.<span> </span>