ATP and Muscle Contraction By: Breanna Paulhamus and Bryce Phillips

ATP is the energy source for muscle contraction Muscle contractions require large amounts of energy Skeletal muscles require 600 trillion contractions each second Muscle fibers generate ATP at the same time

ATP and CP reserves Primary function is to transfer energy ATP + creatine ADP + CP ATP transfers energy to Creatine Creatine Phosphokinase(CP) are enzyme that regulate reactions The energy stored in in CP is used to recharge ADP back to ATP ( ADP + CP ATP + creatine) Resting muscles have 6 times the amount of creatine phosphate as ATP Energy reserve in 15 seconds

Aerobic Metabolism Occurs in the mitochondria Provides 95% of ATP needed by a resting cell Substrates go through the citric acid cycle Oxygen supply creates ATP aerobic production

Glycolysis It breaks down glucose inside of the cytoplasm in the cell It breaks down into pyruvate Pyruvate is converted into lactic acid which potentially causes a pH problem in the cells

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Muscle Fatigue occurs when there is a depletion of energy reserves or a decrease in pH This means that the muscles will no longer contract if they are stimulated

Recovery Period This is the time after muscle activity that it takes to restore prexertions and conditions Requires the person to breathe faster so that they can reduce the oxygen debt Blood vessels in the skin will begin to dilate, causing sweat The sweat will begin to evaporate and cool the body

Heat Loss Muscle activity generates heat Heat warms the sarcoplasm, interstitial fluid and circulates blood Shivering keeps you warm in cold conditions When skeletal muscles contract the heat level peaks and body temperature soon rises

Checkpoint Questions 13. How do muscles cells continuously synthesize ATP? By utilizing creatine phosphate and metabolizing glycogen and fatty acids. Most cells generate ATP only through aerobic metabolism in the mitochondria and through glycolysis in the cytoplasm 14. What is muscle fatigue? A muscle's reduced ability to contract due to low pH (lactic acid buildup and its dissociation to lactate and a hydrogen ion), low ATP levels, or other problems 15. Define oxygen debt The amount of oxygen required to restore normal, pre-exertion conditions in muscle tissue