Do we respire anaerobically when we go unconscious in water and we are out of oxygen?
no we don't respire anaerobically. when submersed completely in water and when our lung get's deprived of oxygen and we will start to struggle in search of oxygen if it takes too long.
Breathing is one of the few bodily functions which, within limits, can be controlled both consciously and unconsciously. We always breath aerobically. Unconsciously, breathing is controlled by specialized centers in the brainstem, which automatically regulate the rate and depth of breathing depending on the body’s needs at any time.
maybe our cells go under anaerobic processes, but we are not anaerobic creatures . the time the amount of oxygen transfer is not enough for the cell to produce energy, the cells go under a pathway which produce lactic acid instead of CO2, the process that happens to athletes, (such as football plyers before penalty kicks!)
No, If oxygen is not available, our cells die. They cannot generate ATPs if oxygen is not available. In absence of oxygen, only two molecules of ATP are formed per molecule of glucose, instead of 38 molecules of ATP as when oxygen is present. For all practical purposes if oxygen is absent, our cells (and ultimately us) will die.
a question Prasadwaghnare; in absence of oxygen do our cells die or do they form two molecules of ATP? you said two different things in two sentences.
To begin with i think i might briefly mention exactly what is the role of oxygen in respiration. When glucose enters cell it first undergoes glycolysis which yields pyruvate. Pyruvate then enters krebs cycle which produces reducing equivalents (NADH and FADH2) these reducing equivalents now enter oxidative phosphorylation where oxygen acts as electron acceptor. It is the oxidative phosphorylation which produces majority of the ATPs (around 36) that a glucose molecule yields. Now in anaerobic bacteria there is a mechanism by which some other element like sulphur acts as electron acceptor in above mentioned reaction. It is prudent that cells cannot survive only on the two ATPs produced via glycolysis (the exception is RBCs which can survive because their structure is very simple, lacking any cell organelles), electron transport chain reaction (oxidative phosphorylation in our case) is very much needed for survival. Our cells are designed to use oxygen for that reaction. (anaerobic bacteria use some other element) Thats why our cells will die in absence of oxygen.
Prasadwaghnare, Does the process involve active transport of H+ ions from the NADH and FADH2 and into other membrane channels for ADP to become ATP?