maintaining the supply of ATP

• the ATP vavailable in muscle tissue is only enough to support at most 1 - 2 seconds of contraction. ATP must be regenerated very quickly to allow continued contractions, the following 3 mechanisms maintain the supply of ATP:

  Aerobic respiration in mitochondria

  Anaerobic respiration in the sarcoplasm of the muscle tissue

  Creatine phosphate in the sarcoplasm, acting as a store of phosphate groups.
• How does Aerobic respiration in the mitochondria help to maintain the supply of ATP in the muscles?

  Muscle tissue contains a large number of mitochondria in which haerobic respiration takes place. the Bohr effect helps release more oxygen from the haemoglobin in the blood. however during intense activity,, the rate at which ATP can be produced will be limited by the delivery of oxygen to the muscle tissue.
• How does Anaerobic respiration in the sarcoplasm help maintain the supply of ATP in the muscles?


  Anaerobic respiration can release a little more ATP from the respiratory substrates. However, it leads to the production and build up of lactic acid which is toxic. anaerobic respiration can only last for a few seconds before lactic acid build up causes fatigue.
• how does creatine phosphate in the sarcoplasm acting as a reserve fof phosphate groups help aid in the maintenance of the supply of ATP in the muscles?

  The phosphate can be transferred from the creatine phosphate to ADP (Adeno di phosphate) molecules to create adeno tri phosphate molecules very rapidly. The enzyme creatine phosphotransferase is involved. The supply of creatine phosphate is sufficient to support muscular contraction for a further 2 - 4 seconds.