The Earth is layered because of the difference in the density and the pressure experienced by the elements. The denser layers tend to be closer to the center and the lighter layers float on the top. The differences in the pressure experienced by these layers also keeps them separated. The pressure experienced by the center of the Earth is greater than the upper layers, and hence, the core is in liquid form because the pressure is not enough for it to remain in the solid state.
This led to the layering of the Earth's surface.
The correct answer is (c) discover antigens in body fluids.
B lymphocytes act as antigen presenting cells that recognizes and displays the antigen to the white blood cells. These cells process the antigens that are present in body fluids. Professional antigen presenting cells includes B-lymphocytes, macrophages, dendritic cells, etc.
Answer: Option B
Explanation:
Usually in scientific experiments, at least one parameter is checked; here, the growth rate of wheat in two different conditions is being evaluated.
Hence, growth rate of wheat alone in pans A, B and C becomes the standard or referential control against which the experimental control (Wheat + clover) in pans D, E and F is evaluated, since both treatments are exposed to the same external conditions.
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