What are the reactions by which muscle fibers produce ATP?

Answer 1

Muscle cells make energy to because when they contract the mitochondria produces or uses (i don't really know which one... by the way im in grade 8) the ATP energy. and that is how muscles use energy. oh yeah one more thing muscles have more mitochondria than any other cells. (ex... skin, nerve stc...)

- Teeya

Answer 2

ATP is always stored in the body but the amount in the body can only last 2 or 3 seconds. When it is used it is broken down from one adenozine and three phosphate moleclues into adenzine diphosphate (2 phosphate molecules) and a sepreate phosphate molecule. This reaction is exothermic and produces energy.

There are three main ways it can be resynthesised (the phosphate molecule rejoining the ADP [adenozine diphosphate) and these are by using the phospho-creatine system, the lactic system and the aerobic system.

The phospho creatine system simply uses the energy from phospho creatine to reattach the P to the ADP, however there is a limited amount of creatine in the body so this can not be used for activity lasting longer then 10 seconds.

The lactic system uses carbohydrates (glucose) in the form glycogen (which is stored in the muscles and liver). It uses the enzyme phosphofructokinase (PFK) to break the glycogen down into pyruvic acid and then uses the enzyme lactic dehydralase (LDH) to break the pyruvic acid down to lactic acid. This resynthesis 2 ATP molecules and leaves lactic acid as a waste product. It can be used for up to 2 minuites before the levels of lactic become too high.

Aerobic resipration is much more complicated as oxygen is present. It starts the same way as lactic respiration but as oxygen is present, there is no lactic acid formed, instead pyruvic acid is converted into acetyle CoA by the enzyme coenzyme A. The acetyle CoA is then converted into citric acid by oxaloacetic acid. The citric acid then goes through something called the Krebs cycle where everything produced in respiration except the energy is removed. This leaves 2 ATP molecules. The hydrogen removed from the reaction then is converted using something called an electron transfer chain into 34 ATP molecules and water.

GLT

Answer 3

Muscle cells and all other cells in the human body make ATP all the time.