Natural selection act directly upon <u>Alleles</u>
Explanation:
Genes, such as that of fur color, have many variants called alleles. Natural selection act on the alleles and chooses the best fit for an environment and eliminates the disadvantageous ones from the population over generations. Mutations are a rare occurrence that increases the number of allelic variants of a genes on which natural selection can act upon.
Answer:
Increase in eosinophils.
Explanation:
The leukocytes are the white blood cell that plays an important role in the immune system. The white blood cell include eosinophil, basophil, neutrophil and monocytes.
The allergic reactions that are caused by hay fever or asthma is marked by the excess increase in the number of eosinophils in the body. The eosinophils are the first to reach at the site of parasitic infections and protect the body during the allergic reactions.
Thus, the answer is eosinophils.
Answer:
Coal.
Explanation:
Steam power plant has the lowest efficiency in electricity production which can only be run with the use of fossil fuels such as coal. The efficiency of this power plant is the lowest because large amount of coal is converted into smoke and other gases and very less amount of coal into heat energy. This coal is used to produce heat energy which can be used in the heating of water to produce steam. This steam is used to move turbines which turn mechanical energy into electric energy.