Exam Review Notes

Dyspnea is defined as difficulty breathing.
Difficulty breathing leads to not getting enough oxygen.
The question was about what dyspnea is associated with, not what it could lead to.

Apnea: No breathing at all. The prefix "a" means without.
Eupnea: Normal breathing.
Normal breaths per minute: 12 to 20.
Hyperventilation: Breathing more than normal (above 20 breaths per minute), resulting in getting more oxygen.
Hypoventilation: Breathing less than normal (below 12 breaths per minute), resulting in getting less oxygen.
Dyspnea is associated with hypoventilation because difficulty breathing means not getting enough oxygen.

Avoid thinking about the next possible steps or scenarios when answering questions.
Focus on what the question is directly asking.
Do not assume the question is trying to trick you; read it carefully and answer what it's asking directly.

Air distribution is the process of air moving from one point to another within the body.
It's like FedEx, distributing air throughout the body.
Air distribution structures: Nose, pharynx, larynx, trachea, primary, secondary, tertiary bronchioles
All structures except the alveoli are air distribution organs; they are essentially tubes.
Air or oxygen distribution refers to the same process.

The alveoli are air sacs in the lungs where oxygen and carbon dioxide are exchanged.
Millions of alveoli in the lungs expand and contract.
Oxygen inhaled through the nose, pharynx, larynx, trachea, and bronchioles reaches the alveoli, filling them like balloons.
Capillaries surround the alveoli but do not touch them; they carry deoxygenated blood.
Through diffusion, carbon dioxide moves from capillaries to alveoli, and oxygen moves from alveoli to capillaries.
After oxygen is absorbed, carbon dioxide is exhaled.
Oxygen-filled capillaries then distribute oxygen to the rest of the cells via the circulatory system.

Exchange of oxygen and carbon dioxide between the alveoli and blood in the lungs.
Called "external" because the air is coming from the outside.

Exchange of oxygen and carbon dioxide between blood and cells throughout the body.
Capillaries distribute oxygen to the rest of the cells in the body.

The most important muscle for inspiration (breathing in) is the diaphragm.
When you breathe in, your lungs expand, and the diaphragm pushes down, creating more space for the chest to expand.
During inspiration, the chest expands, and the abdomen appears smaller as the diaphragm pushes down.
For expiration, abdominal muscles and intercostals would be involved.

The sole purpose of the epiglottis is to prevent food from entering the trachea.
It's a flap that covers the trachea when swallowing food, directing it down the esophagus.
When breathing, the epiglottis covers the esophagus, allowing air to enter the trachea.

Trachea is in the front (anterior).
Esophagus is in the back (posterior).
The epiglottis covers the trachea when swallowing.
Sometimes, if the epiglottis malfunctions (e.g., when laughing while eating), food or liquid can enter the nose.

Epiglottitis is a condition where the epiglottis becomes infected and enlarged, causing discomfort.

Alveolar ducts, which are smaller than bronchioles, are the smallest air distribution tubes, connecting to the alveoli.