Answer: A variety of substances will dissolve oil, including gasoline and carbon tetrachloride -- both of which have non-polar molecules. Acetone is a special class of solvent called “dipolar aprotic” that, depending on the circumstances, can act as a weak acid or base; it dissolves oil and mixes with water as well.
Explanation:
Answer:
Innate immunity is a non-specific immune system which provides defence against any pathogenic microorganism in early stages. It includes physical barrier such as skin, chemical barriers such as saliva, tears, et cetera, phagocytic cells such as macrophages, et cetera.
Acquired immune system is the one which develops after exposure to pathogen or antigen. It is highly specific in nature. It includes B-lymphocytes and T-lymphocytes. It includes the production of antibodies.
Vaccines are used to develop acquired immunity in people. The process is termed as vaccination or immunisation. Heat-killed or weakened pathogen or antigen is inserted into a person after which a person develops antibodies and memory cells against that pathogen or disease. So, the immune system acts more vigorously against that pathogen in secondary infection.
Thus, a person becomes immunised.
Answer:
The correct answer would be - d. With the end of genetic isolation gene flow took place
Explanation:
It is given that people of Troublesome Creek Kentucky were isolated and have a rare recessive allele that results in a blue tone to their skin. However, later these isolated people connected with the people from outside, and due which allow them to intermate. Intermating among populations from isolated and people from outside leads to gene flow.
Methemoglobinemia was present in the isolated population as they had both recessive alleles in their genotype and other hand people from outside might have heterozygous or both dominant allele genotypes that make them free from this disorder.
Due to the intermating and gene flow, the number of heterozygous conditions rises and after many generations slowly methemoglobinemia could have disappeared due to the masked recessive allele.