Answer:
Muscle contraction is the activation of tension-generating sites within muscle fibers. In physiology, muscle contraction does not necessarily mean muscle shortening because muscle tension can be produced without changes in muscle length, such as by holding a heavy book or a dumbbell at the same position. The termination of muscle contraction is followed by muscle relaxation, which is a return of the muscle fibers to their low tension-generating state.
Explanation:
Answer:
In a patient who has low blood oxygen levels, although his blood is circulating properly, is most likely that alveoli are functioning improperly.
Explanation:
The supply of oxygen to the blood depends on the breathing process, performed by the respiratory system.
At the level of the pulmonary alveoli occurs gaseous exchange, this is the entry of oxygen from the inspired air and the elimination of CO₂ resulting from cell metabolism. If the alveoli do not function properly, the gas exchange will be deficient and there will not be enough oxygen in the blood and tissues.
The other options are not correct because of:
<u><em>Capillaries
, aorta and pulmonary vein </em></u><em>are part of the circulatory system, on which the oxygenation of the tissues depends, not the oxygen content of the blood.</em>