Ans.
Sickle-cell disorder is a genetic disorder, which shows defected red blood cells, due to mutation in the genes for hemoglobin protein.
Malaria is common in sub-Saharan Africa region and there, natural selection favored gene for sickle cells, because it might be beneficial to people having sickle cell disease that makes them able to survive in such condition and transmit their genes to offspring.
On the other hand, in those Africans, who moved to United States, where malaria is uncommon or absent, natural selection favored normal, wild type genes, resulting in fewer people with defected sickle cell.
Hence, sub-Saharan African population shows higher percentage of mutated gene for sickle cell as compared to population of United States.
Thus, the evolutionary process behind this difference is 'natural selection.'
The answer is B hope this helped!
An experiment is created by a scientist to determine how fertiliser affects sugar cane height. Two fields receive fertilization, but the remaining two do not. Fertilizer Application serves as the experiment's control group.
Fertilizer Application is typically limited to irrigated plantations and varies by region and even by farmer. Fertilizers will work best if used between 12 and 24 months before and after the peak growing season. One year after planting, farmers typically spray 50 kg of urea and 50-100 kg of DAP per acre. Since Casuarina manufactures its own nitrogen with the aid of the bacterium Frankia, it does not require a significant amount of nitrogen fertiliser. In order to prevent this, it is advised to apply 11 kg of urea and 94 kg of superphosphate at moderate level.
Learn more about Fertilizer Application here
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Answer:
Always include the steps and/or background required to get to the final answer. Let’s help other people understand and solve future problems on their own. Explanation:
Most peripheral nerves are nerves outside the brain and the spinal cord, carrying both sensory and motor impulses. The peripheral nervous system is one of the two components of the nervous system, the other part is the central nervous system. Peripheral nerves are classified into motor, sensory and autonomic nerves.
