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.
Anaerobic respiration is the process by which non-oxygen dependentorganisms breath. It is mostly commonly used in the process offermentation.Anaerobic respiration is respiration that uses electron acceptorsother than oxygen. Anaerobic respiration can be found in protozoansand bacteria. Anaerobic respiration is a type of cellular respiration. It occurswhen oxygen is not available or is available in very lowquantities. It is also a respiration in the absence of oxygen.