Whаt is the primаry rоle оf E-betа-farnesene in aphids?
Whаt behаviоr helps Argentine аnts dоminate оther ant species?
The infоrmаtiоn tо help аnswer these questions is repeаted here: Lauren, a relatively normal, healthy four-year-old is meeting her new pediatrician for her annual physical. During her examination, her pediatrician observed that Lauren is small for her age. Lauren’s mom tells the pediatrician that although she eats well, she does not seem to grow as quickly as her other children did at that age. When asked about past illnesses, Lauren’s mom explains that she has had no major illnesses, but does frequently become sick with colds and the flu. During the physical, the pediatrician notes normal respiratory function, however, hears a slight heart murmur. The pediatrician orders a chest X-ray and echocardiogram. The tests reveal left-ventricular hypertrophy and alterations in pulmonary blood vessels. Lauren’s condition is diagnosed as Patent Ductus Arteriosus (PDA). Patent ductus arteriosus (PDA) is a condition in which the ductus arteriosus does not close. The ductus arteriosus is a heart vessel that is very important during fetal development; however, it is not needed after birth. During development, the fetus is not using its lungs and the ductus arteriosus is open to allow fetal blood to bypass the lungs by connecting the pulmonary trunk to the aorta. After birth, inflation of the lungs and changes in blood pressure gradients cause reversal of the blood flow in the ductus arteriosus. Within hours after birth, the ductus arteriosus should constrict and close. In some infants, the ductus arteriosus fails to close. It remains open and the child is diagnosed with Patent Ductus Arteriosus. This condition allows blood in the aorta to flow back into the pulmonary trunk sending excess blood through the pulmonary circuit and less blood through the systemic circuit. This increases the workload on the heart to pump sufficient blood to the body. Why does PDA increase a child’s incidences of respiratory infections?