The second option: meiosis and fertilization
process A is meiosis, you can see that the gamete(haploid cell) results from the diploid cell. The gamete has n chromosomes(39), whereas the diploid cell has 2n(78)
process B is fertilization the two gametes(haploid) fuse together to form the zygote(diploid)
Answer: Hereditary carrier or carrier
A hereditary carrier is a person or an organism that has inherited a recessive allele. Alleles are pairs or series of genes on a chromosome that determines hereditary characteristics. Carriers have the genetic trait but do not show the trait or show symptoms of any disease.
Cell Replication happens in S phase
The Prader-Willi syndrome (PWS) is due to the lack of expression of paternal genes of the 15q11-q13 region. It usually occurs sporadically, although some family cases have been described (<1%). Approximately 70% of cases are produced by deletions of paternal origin in the 15q11-q13 region. 28% of cases are due to maternal uniparental disomy and less than 2% are caused by imprinting alterations. A geneticist studying prader-willi syndrome should focus on chromosome 15, its structure or changes in the number, these anomalies are also related to other syndromes such as: Bloom Syndrome, Breast cancer, Isovaleric acidity among others.
