Question

Some poisons directly affect the process of cellular respiration. Do your best to outline step by step the consequences of these poisons:

a. If a poison stopped hemoglobin in your red blood cells from binding oxygen, what would happen to your cells? (Why is oxygen needed to produce high amounts of ATP in cellular respiration?)

b. If a poison blocked the enzymes of the Krebs Cycle, what would happen?

c. If a poison blocked the flow of electrons in the electron transport chain, what would happen?

Answer 1

If a poison stopped hemoglobin in your red blood cells from binding oxygen, what would happen to your cells? (Why is oxygen needed to produce high amounts of ATP in cellular respiration?)

If hemoglobin is not able to bind the oxygen, as hemoglobin is the molecule which is involved in transferring oxygen to various cells in our body, cells will not get oxygen supply. Important organs like brain, heart etc. will not get oxygen and will start dying. Cellular respiration needs the oxygen and is supplied from the lungs with the help hemoglobin and for our cells, ATP is the main energy currency and glucose needs to converted to ATP and 40% of the glucose provided energy will result in ATP and in the absence of oxygen, only 2% of the available energy only will be converted to ATP. In cellular respiration, the energy will be released when electron will move from their high energy state to low energy state and the hydrogen which is moving along with it, will be combining with oxygen after splitting off from glucose and energy will be released and oxygen forms water by combining with hydrogen. So, in the absence of oxygen, the ETC wont function, so major amount of ATP production will be affected.

If a poison blocked the enzymes of the Krebs Cycle, what would happen?

Mitochondria is involved in energy production and any disruption in this process will lead to serious metabolic symptoms. Krebs cycle occurs inside the mitochondria and are involved in energy production and the main function of Krebs cycle is metabolizing the acetyl CoA into the citric acid cycle, through a series of reaction, the cycle produces hydrogen ions with a net production of 2 ATPs. The produced hydrogen ions then enter the oxidative phosphorylation, which yields 34 to 36 ATP molecules and finally these hydrogen electrons will combine with oxygen to from water. So net gain of 38 ATPs cell will obtain when citric acid rotates through Krebs and ETC. When poison interferes with Krebs cycle, there will not will be release of hydrogen ions, so ETC will be interrupted. No ATP production will be there.

If a poison blocked the flow of electrons in the electron transport chain, what would happen?

The transmembrane proton electrochemical gradient will be produced during the electron transport chain because of redox reaction. Here electrons will be transferred through a series of compounds and the electron transfer will be coupled with proton transfer across the membrane and this help us to synthesize the ATP molecules. At the end of the chain oxygen will accept the electrons. ETC will yield 34 or 36 ATP molecule, and when poison blocks the electron flow, the ATP synthesis will be affected and cell will not get their energy.