Answer:
a is perpendicular to c will be the answer.
Answer: B (Color blindness)
Explanation:
Typical red-green color blindness in human patients is caused by mutations on genes located in the X chromosome. These mutations act in a recessive manner. Since females have two X chromosomes, the presence of a mutation in a single one of them does not normally result in color blindness. Males, in contrast, have a single X chromosome and therefore the presence of a mutation is likely to cause the disease.
About the other options: Down‘s syndrome is a numerical chromosomal anomaly, not related to sex. Human blood type is a codominant trait. Finally, tail length in dogs is a polygenic trait not amenable to classic Mendelian analysis.
Photosynthetis, burning of fossil fuels, plant respiration.
Ans.
Sickle-cell disorder shows defected red blood cells, due to mutation in gene that code for hemoglobin. The mutated genes for sickle-cell disease are found in higher percentage of sub-Saharan African population as it provides protection against malaria as compared to population of United States.
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.
Thus, the evolutionary process behind this is 'natural selection.'