MEDICINE ACTIVITY

1. It doesnâ€™t enter the nasal cavity because the soft palate moves upwards and blocks the nasal pathway. When we laugh at a joke, we exhalate which makes the soft palate move downwards and the food can access the nasal cavity.

2. Functionally, the respiratory system divides into the conduction zone and the respiratory zone. The conduction zone, as the name states, is where the air is conducted from the first part of the respiratory system until the terminal bronchioles, and here the air is warmed and filtered by the respiratory cilia. The respiratory zone is from the terminal bronchioles to the alveoli, where respiration takes place, and when oxygen is exchanged from the carbon dioxide present in the alveolar capillaries.

3. Phonation begins when exhalation increases the pressure below the glottis, forcing it to open and letting the air pass through the vocal folds, which causes them to wave. The glottis closes again after the pressure drops, repeating the cycle after each exhalation. This is controlled by innervation of cerebral nuclei and cortex. The inability to phonate or aphonia occurs when a person canâ€™t increase properly the subglottic pressure to make the glottic open and led the air to pass through and set the vocal cords in oscillation, which occurs in laryngitis.

4. The larynx is an important organ, constituting a functional sphincter between the respiratory and digestive systems, and is in charge of functions such as phonation, respiration, and deglutition. This organ has 9 cartilages: 3 individuals which are the thyroid cartilage, cricoid cartilage, and epiglottis; and the rest of them are 3 pairs of cartilages which are the arytenoid cartilages, corniculate and cuneiform cartilages.

Laryngitis is a swelling of the larynx caused by respiratory viruses, such as rhinovirus or adenovirus, or by noninfectious causes, which make the vocal cords edematous and less prone to wave when air passes through the glottis.

5. The conductive zone structures are the nasal cavity, the pharynx, the larynx, the trachea, bronchi, and bronchioles. The respiratory zone is from the terminal bronchioles to the respiratory alveoli.

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