Question

Read the following passage and construct a flow chart by matching the following events with their proper sequence. Physical exercise results in skeletal muscle contraction, an active process that requires chemical energy in the form of ATP. Initially, as contractions begin, small amounts of ATP are available within the skeletal muscle fibers; however, because of the limited stores of ATP, contractions may only be sustained for about 15 seconds before the ATP needs to be replenished. Cellular respiration is one mechanism by which muscle fibers produce and replenish their ATP. While cellular respiration increases the availability of ATP, it does so by consuming oxygen and glucose while producing water and carbon dioxide as a waste byproduct. Thus, during exercise, as the metabolic activity of the muscle fibers increase, the concentration of oxygen in the muscle tissue decreases. Other byproducts of metabolic activity (temperature, acidity, and CO2 concentrations) also increase as the muscle fibers continue to contract and consume glucose and oxygen. The increased presence of these metabolic byproducts are detected by specific homeostatic sensors that send out signals to the local vasculature and cause vasodilation, thereby shifting blood flow from less active tissues to the nearby exercising muscles. The greater flow of blood into the exercising muscle resolves the oxygen loss while simultaneously removing the waste and other byproducts of the increased metabolic activity.

Answer 1

Answer:

Person starts to exercise.

Skeletal muscle oxygen demand increase  

Skeletal muscle metabolism increases

.Blood delivery to the skeletal muscle increases is order to provide more oxygen  

Oxygen sensors cause local blood cell vessels to dilate

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This steps briefly describe the physiology of exercise.

At the onset of exercise,  skeletal muscles cells were sustained with  available oxygen from the Myoglobin. Myoglobin is  oxygen binding and storage  protein found in cardiac and skeletal muscles cells.  it has high storing capacity for oxygen.

However as the exercise becomes intense ATPs supply drops, oxygen  demand increases,cellular metabolisms demand also increase to supply glucose and ATP to the cells.

The liver mediates Gluconeogenesis.  Fatty acid is broken down to glucose for cellular respiration  with' ketone bodies  build up..Exercise also stimulates the breakdown of muscle glycogen to glucose,  Therefore, cellular respiration takes place to break down the glucose to  C02, H20  and energy with rise in temperature.

However, oxygen concentration is  low, therefore muscles cells undergo anaerobic respiration with lactic acid pathway. Lactic  acid  build up in muscles cells.The muscles cells under go oxygen debt to break down  lactic acid  to glucose in muscle.

Therefore to adjust the mechanism oxygen homeostatic sensors increases hyperventilation to increase  oxygen intake through the lungs, and vasodilation. so that maximum volume of blood containing oxygen is transported to muscles cells; to sustain the intense activity

 

 

Explanation: