How is water critical for respiration?
The correct answer and explanation is:
Correct Answer:
Water is critical for respiration because it is a product of aerobic respiration and is essential for the transport of gases and biochemical reactions involved in the process.
Explanation (300 words):
Water plays a central role in the process of respiration, particularly aerobic respiration, which takes place in the cells of organisms to produce energy. In this type of respiration, glucose reacts with oxygen to produce carbon dioxide, water, and energy in the form of adenosine triphosphate (ATP). The overall chemical equation for aerobic respiration is:
C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + energy (ATP)
From this equation, it is clear that water is a byproduct of the reaction. This water is formed when hydrogen ions and electrons, transferred along the electron transport chain in the mitochondria, combine with oxygen at the end of the chain. Without oxygen to accept the electrons and form water, the electron transport chain would stop, halting the production of ATP.
Apart from being a product, water is also essential in the early stages of respiration. The cytoplasm, where glycolysis (the first step in cellular respiration) occurs, is a watery environment. Water allows enzymes to function properly and supports the transport of glucose and other molecules. Enzymes responsible for breaking down glucose and transferring electrons need water to maintain their structure and activity.
Additionally, water helps regulate body temperature, supports circulation, and aids in the transport of oxygen and nutrients to cells. Oxygen, necessary for aerobic respiration, is dissolved in blood plasma, which is mostly water, and carried by red blood cells.
In summary, water is vital in both the formation of ATP through aerobic respiration and in maintaining the cellular environment necessary for the various biochemical steps of respiration to occur efficiently.