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 burn can be classified as the partial-thickness second degree burn.
The symptoms of the second degree burns are sensitive wound base, painful blisters, the surface may be blanched on applying pressure, erythematous or fibrinous exudate is present.
In the given case, the person burns the hand with scalding water. The symptoms of the burn shows red area, pain, and blisters. These are the symptoms of the partial thickness second degree burn, which affects the epidermis and dermis.
Answer:
The major organs of the nervous system are the brain, spinal cord, sensory organs, and all of the nerves that connect these organs together.
The nervous system reacts to the presence of danger(instinct), stores memories, control the 5 senses, and commands the rest of the organ systems to maintain homeostasis.
The nervous system works together with the respiratory system, the circulatory system, the muscular system, and many more.
Fitness. Give me brainliest please
