Melatonin is produced in the hypothalamus gland
The benefit of the circuit of fetal blood course through the ductus arteriosus is the ductus arteriosus will permit more blood to go to the placenta and sidestep the lungs (since there is no blood required there yet). I hope the answer will help you.
Heres 4, pick your favorites haha
.Trying to Keep Up with Others
.Forgetting About the Unexpected
.Using Outdated Software
.Forgetting About the Small Items