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.
This page is about external respiration, which is the processes by which external air is drawn. the body in order to supply the lungs with oxygen, and (used) air is expelled. the lungs in order to remove carbon dioxide from to body. (The processes of internal respiration concern the exchange of gases in the lungs with those in the tissues and is described on the next page). Inspiration (= inhalation). Concentration of Gases. Expiration (= exhalation). 1. Intercostal muscles contract. 2.