Problem 15: Metabolism During Heart Attack

[Anonymous]

Problem 15: Metabolism During Heart Attack
During a heart attack, blood flowing to the heart muscle is interrupted by blockage of a coronary artery. How would you expect the metabolism in the heart to change?

A. oxidative phosphorylation would slow down in the mitochondria
B. the rate of production of lactic acid would be stimulated

C. the use of glucose by the muscle tissue would increase

D. the production of water by mitochondria would be inhibited

E. all are expected metabolic changes


Effects of a heart attack on heart metabolism
Reducing blood flow to the heart restricts oxygen delivery. This slows oxidative phosphorylation in mitochondria rerquiring the cell to resort to fermentation, producing lactic acid to regenerate NAD+ for glycolysis. Since glycolysis can only product ATP, the amount of glucose needed for energy increases exhausting stores of glycogen. Water is produced when oxygen serves as the terminal electron acceptor. Thus, without oxygen the production of water from electron transport is severely inhibited.

ans:

E. all are expected metabolic changes


Arteries carry oxygenated blood. If the flow of blood through the coronary artery to the heart is blocked, the heart is being deprived of oxygen. All of the above answers are expected effects of an insufficient oxygen supply to the cells, and resulting fermentation.