Final answer:
The exact length of the trachea in premature and full-term newborns is not provided in the information given. Newborns average 51 cm in total body length at birth, but specific tracheal measurements are not mentioned.
Step-by-step explanation:
The question asks about the length of the trachea in both premature and term newborns. While the provided data does not give a specific answer to the length of the trachea, it provides context about the growth and development of infants both before and after birth. We know that a full-term newborn's average total body length is about 51 cm at birth and that all measurements of the infant post-birth are made from head-to-toe. Considering the differences between pre-term and full-term infants, especially in terms of growth and development, and the fact that fetal growth in the last trimester is focused on weight gain and development necessary for survival outside the womb, it can be deduced that premature infants will have shorter tracheas than term infants. Unfortunately, without specific anatomical data on tracheal length in neonates, providing an exact length for either premature or full-term newborns is not possible.