Question

Please write 1 paragraph for each of the following (total 3 paragraphs) and each paragraph shall be no less than 3 sentences and no more than 6 sentences.

Main Post

1. Discuss the path of air flow from the atmosphere all the way down to the alveoli of the lungs or the mechanisms of breathing: how does air move in or out of the lungs
2. Discuss the different volumes that are considered during ventilation/breathing (tidal, end respiratory reserve, vital capacity, etc….)
3. Discuss the stages of stress as experienced by a human being

kindly provide references, thanks

Answer 1

1. Air enters the lungs from atmosphere through external nostrils--->nasal cavity--->internal nostrils--->nasopharynx--->laryngopharynx--->trachea--->principle bronchus--->primary bronchiole--->secondary bronchiole--->tertiary bronchiole---> alveolus. The air exits through the same above mentioned flowchart. The oxygen is inhaled and the carbon dioxide is exhaled during breathing.

2. The volume considered during breathing are:-

1. Tidal Volume:- It is the amount of air inhaled or exhaled during normal breathing. It is about 500ml.

2. Residual Volume:- It is the amount of air left in lungs even after forceful exhalation. It is about 1200ml.

3. Inspiratory Reserve Volume:- It is the amount of air which one can inhale during forceful inspiration. It is about 2000 ml.

4. Expiratory Reserve Volume:- It is the amount of air which one can exhale during forceful exhalation. It is about 1100ml.

5. Vital capacity:- It is the maximum amount of air one can exhale after maximum inhalation. It includes tidal volume, inspiratory reserve volume and expiratory reserve volume. It is about 4800ml.

3. There are generally 3 stages of stress experienced by humans:-

1. Alarm. 2. Resistance. 3. Exhaustion.

1. Alarm:- The alarm stage is generally a caution stage in which body alters conditions to cope with stress. These alterations come in the form of flight and fight reactions like, the blood circulation is increased etc.

2. Resistance:- Resistance is the prolonged form of alarm stage in which the body prepares for the long term effects of alarm stage, like increase in blood circulation and then making it flow at a constant rate. Increase in the secretion of adrenaline and noradrenaline and then again secreting it at a constant rate.

3. Exhaustion:- If there is no time gap given to recover in between stress it can lead to exhaustion as no more substances can be released in comparison to already released substances in flight or fight reactions.