One explanation could be the differences in climate (environmental factors). The climate in northern Mexico could support the reproduction of the mosquito species, which is a vector of the dengue virus. Other environmental conditions that influence its endemicity could include living conditions and sanitation. The other possiblity could be that the people in the US have developed immunity for the disease, therefore, are unaffected even when infected by the virus.
Answer:
Pregnancy, which is characteristically associated with changes in hormone levels in the body is a process tightly regulated by the hormon Human Chorionic Gonadotropin
Explanation:
The so-called pregnancy hormone is the Human Chorionic Gonadotropin (HCG). It only occurs during the gestation period and is responsible for regulating the entire process. Segregated by the placenta, it can be found in urine and blood.
The presence of the hormone in the urine allows to confirm the pregnancy with the test. As in pregnancy, the placenta begins to form, the cells that make it up begin to stimulate the production of HCG, which causes the hormone levels to increase very rapidly in the first trimester of pregnancy
Origin of replication
Termination site? I am not too sure about the second one.
