3 - Respiratory Physiology

Flashcards covering the anatomy, mechanics, processes, and exercise responses of the respiratory system based on lecture notes.

Ventilation

The process of moving air in and out of the lungs, commonly known as breathing.

Respiration

The process of exchanging gases, specifically $O_2$ and $CO_2$, between the blood and lungs or the blood and tissues.

Pulmonary Respiration

The process of gas exchange occurring at the lungs where $O_2$ is infused into the blood and $CO_2$ is removed from the blood.

Cellular Respiration

The process of infusing $O_2$ into and removing $CO_2$ from the body's tissues.

Pharynx

Also known as the throat, this anatomical component is used for both breathing (air) and digestion (food).

Larynx

Also known as the voice box, it is located inferior to the pharynx and superior to the trachea and is used only for breathing.

Trachea

The windpipe; a singular muscular tube held vertical and open by tracheal cartilage that eventually forks into the bronchi.

Bronchi

The two tubes branching from the trachea that enter the lungs and further split into the bronchial tree.

Alveoli

Small, bubble-like sacs with very thin walls responsible for gas exchange; an average human has approximately $300\text{ million}$ of them.

Conducting Zone

The functional zone of the respiratory system where air is transported from the nose or mouth into the lungs.

Respiratory Zone

The functional zone of the respiratory system where gas exchange takes place once air reaches the lungs.

Boyle's Law

A law stating that the pressure of a gas is inversely proportional to its volume ($P \times V = k$).

Diaphragm

A dome-shaped muscle nicknamed the 'umbrella muscle' that flattens when contracted to increase lung volume.

Inhalation

The process of bringing air into the lungs when the diaphragm pushes downward, ribs lift outward, lung volume increases, and lung pressure decreases.

Exhalation

The process of moving air out of the lungs when the diaphragm relaxes, ribs pull downward, lung volume decreases, and lung pressure increases.

Respiratory Rate (Rest)

The number of breaths taken each minute at rest, which is approximately $12\text{ breaths/min}$.

Tidal Volume (Rest)

The volume of air taken in with each breath at rest, which is approximately $500,mL$.

Anticipatory Rise

An increase in heart rate and ventilation that occurs immediately prior to exercise, initiated by the nervous system.

Ventilatory Threshold

The point during exercise, occurring after a linear increase up to 75\text{%} $VO_2\text{max}$, where ventilation begins to increase exponentially.

Respiratory Control Centre

The area located in the brain stem that is primarily responsible for regulating ventilation.

Chemoreceptors

Sensors found in the aorta and carotid arteries that detect blood composition and increase the urge to breathe in response to an increase in $CO_2$.

Spirometer

A device that can detect air flow to measure ventilation and sometimes identify gas composition to measure respiration.