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.
Cellular processes get usable energy from a process called respiration. Respiration commonly involves the use of oxygen to break down carbohydrates and other organic molecules, giving usable energy, carbon dioxide and water in the process. All organisms breatheâa process in which they take in oxygen and give off carbon dioxide. This is called external respiration.