Assignment 5 Part A – Carbon dioxide transport Drag each label to the appropriate location on the flowchart. Carbon dioxide is carried to the lungs. Carbon dioxide is released from the mitochondria. Air exits through nose or mouth. Carbon dioxide diffuses into a capillary. Carbon dioxide diffuses into an alveolus. ? ? ? ? ? Reset Help
The Correct Answer and Explanation is:
Correct Order (Flowchart):
- Carbon dioxide is released from the mitochondria.
- Carbon dioxide diffuses into a capillary.
- Carbon dioxide is carried to the lungs.
- Carbon dioxide diffuses into an alveolus.
- Air exits through nose or mouth.
Explanation
Carbon dioxide (CO₂) is a waste product generated during cellular respiration, specifically within the mitochondria of cells. This gas must be transported from body tissues to the lungs to be exhaled. The process involves multiple steps and systems working together, including the circulatory and respiratory systems.
First, carbon dioxide is released from the mitochondria during the breakdown of glucose for energy. This step is part of cellular respiration and occurs in all active body cells.
Once produced, carbon dioxide diffuses into a nearby capillary. Since the concentration of CO₂ is higher in the tissues than in the blood, it naturally moves into the bloodstream. In the blood, CO₂ travels in three main forms: dissolved in plasma, bound to hemoglobin, or as bicarbonate ions.
Next, carbon dioxide is carried to the lungs through the bloodstream. This transport happens via the venous blood, which returns deoxygenated blood rich in carbon dioxide to the heart. The heart then pumps it to the lungs through the pulmonary arteries.
Upon reaching the lungs, carbon dioxide diffuses into an alveolus, the small air sac in the lungs where gas exchange occurs. Because the CO₂ concentration in the blood is higher than in the alveolar air, the gas diffuses out of the blood and into the alveolus.
Finally, air exits through the nose or mouth during exhalation. The diaphragm and other respiratory muscles relax, pushing the air (now rich in CO₂) out of the lungs and into the atmosphere.
This efficient transport system ensures that waste CO₂ is continuously removed from the body, maintaining the necessary pH balance and preventing toxic buildup in the tissues.
