Answer:
B. hydrogen bond
Explanation:
The double helix is held together by hydrogen bonds between the bases
The enamel. For example lemon juice can destroy your enamel it’s like another way that protects the teeth but you should also protect the enamel.
Answer:
genomic imprinting
Explanation:
Genomic imprinting is a mechanism for regulating gene expression that allows expression of only one of the parental alleles, although both alleles are functional. Unlike most genes in which expression is biallelic, genes that are subjected to this mechanism (imprinted genes) have monoalelic expression; By definition, in an imprinted loci, only one allele is active (maternal or paternal), and the inactive is epigenetically marked by histonic modification and / or methylation of cytosines.
Genomic imprinting can cause some disturbances, among them Prader-Willi syndrome, which is a genetic disorder that involves a partial deletion of chromosome 15q on the paternal chromosome.
