The information in pedigrees that is useful for mapping disease genes is sometimes limited. This pedigree shows segregation of neurofibromatosis, which is a fully-penetrant, autosomal dominant condition, and a single nucleotide polymorphism, SNP1, which has alleles G or T. Why is the cross in generation I not useful for determining the degree of linkage between the disease-causing gene NF and SNP1?

the answer is c. it will give up it's valence electron to the other atom.

these muscles maintain the blood pressure in the vessels. the smooth muscles are innervated by nerves of the autonomic nervous system. when the muscles contract, they cause vasoconstriction of the vessels and increase blood pressure. when the muscles relax, they enable vasodilation of the   blood vessels hence reduce blood pressure.