Respiratory distress in premature babies may be caused by lack of

This condition causes episodic spasms of the smooth muscle in the bronchioles causing wheezing.

T cells are specialized to defend against

A mother feeding her infant breast milk is an example of

This is the first line of defense against pathogens

The function of blood is

Conditions that affect the respiratory system and restrict how much air we can get in/out tend to ________ our ph due to increased carbon dioxide levels.

Vaccines stimulate

This is the first line of defense against pathogens

All of these help lymph and venous blood move through the vessels EXCEPT: