Which structure is the site of gas exchange between inhaled air and the bloodstream?Multiple choice question.alveolusprimary bronchustrachealobar bronchus

Break Down the Problem

1. Identify the components of the respiratory system mentioned in the options.
2. Analyze the function of each structure regarding gas exchange.

Relevant Concepts

• Alveolus: The primary site of gas exchange in the lungs where oxygen and carbon dioxide are exchanged with the bloodstream.
• Primary Bronchus: The main airway leading into each lung; does not directly facilitate gas exchange.
• Trachea: The windpipe that connects the throat to the lungs; it also does not facilitate gas exchange directly.
• Lobar Bronchus: Air passages that branch from the primary bronchi; like the primary bronchi, these do not directly engage in gas exchange.

Analysis and Detail

1. Alveolus: Tiny air sacs located at the end of the bronchial tubes. They are surrounded by capillaries, which allows for oxygen to be absorbed into the blood and carbon dioxide to be expelled.
2. Primary Bronchus: Conducts air but does not perform gas exchange.
3. Trachea: Also only conducts air, not involving gas exchange.
4. Lobar Bronchus: Similarly, these are airways without gas exchange functionality.

Verify and Summarize

The alveolus is specifically designed for the process of gas exchange between inhaled air and the bloodstream, making it the correct answer.

Final Answer

Alveolus is the correct answer as it is the primary site of gas exchange between inhaled air and the bloodstream.