what is the defination of respiration?

Answer 1

Respiration is the exchange of waste products produced during metabolism for the molecules necessary to keep metabolism functioning. In humans, respiration exchanges CO2 and H20 for O2. In plants, O2 is the waste product, along with water, while CO2 is the compound that is required to drive all of its metabolic reactions.

Answer 2

The act or process of inhaling and exhaling; breathing. Also called ventilation.
The act or process by which an organism without lungs, such as a fish or plant, exchanges gases with its environment.

The oxidative process occurring within living cells by which the chemical energy of organic molecules is released in a series of metabolic steps involving the consumption of oxygen and the liberation of carbon dioxide and water.
Any of various analogous metabolic processes by which certain organisms, such as fungi and anaerobic bacteria, obtain energy from organic molecules.
Respiration is much more than just breathing; in fact, the term refers to two separate processes, only one of which is the intake and outflow of breath. At least cellular respiration, the process by which organisms convert food into chemical energy, requires oxygen; on the other hand, some forms of respiration are anaerobic, meaning that they require no oxygen. Such is the case, for instance, with some bacteria, such as those that convert ethyl alcohol to vinegar. Likewise, an anaerobic process can take place in human muscle tissue, producing lactic acid—something so painful that it feels as though vinegar itself were being poured on an open sore.

Respiration can be defined as the process by which an organism takes in oxygen and releases carbon dioxide, one in which the circulating medium of the organism (e.g., the blood) comes into contact with air or dissolved gases. Either way, this means more or less the same thing as breathing. In some cases, this meaning of the term is extended to the transfer of oxygen from the lungs to the bloodstream and, eventually, into cells or the release of carbon dioxide from cells into the bloodstream and thence to the lungs, from whence it is expelled to the environment. Sometimes a distinction is made between external respiration, or an exchange of gases with the external environment, and internal respiration, an exchange of gases between the body's cells and the blood, in which the blood itself "bathes" the cells with oxygen and receives carbon dioxide to transfer to the environment.

Answer 3

Breathing

Answer 4

respiration is the process by which oxygen and glucose combine to produce energy.

Answer 5

the process in which energy is realeased from food