What is a Promise Ring. A promise ring, sometimes known as a pre-engagement ring, is a simple piece of jewelry that is given as a symbol of a committed, monogamous relationship. In some cases, the promise ring symbolizes purity and a decision to remain celibate until marriage.
Noun. 1. external respiration-the bodily process of inhalation and exhalation; the process of taking in oxygen from inhaled air and releasing carbon dioxide by exhalation. breathing, respiration, ventilation. artificial respiration-an emergency procedure whereby breathing is maintained artificially.
A. Ventilation is not the same as respiration, which is the actual exchange of gases between the blood and cells. 1) In external respiration, oxygen moves form the alveoli to the blood: carbon dioxide moves in the opposite direction. 2) In internal respiration, oxygen moves form the blood into tissues and vice versa for carbon dioxide.