Pulmonary Ventilation and Gas Exchange

This set of flashcards covers key vocabulary and concepts related to pulmonary ventilation and gas exchange, as discussed in the lecture.

Pulmonary Ventilation

The process of bringing air into the lungs and pushing it out.

Gas Exchange

The exchange of oxygen and CO2 between alveolar air and the blood in the alveolar capillaries.

Alveoli

Small air sacs in the lungs where gas exchange occurs.

Alveolar Capillaries

Tiny blood vessels that surround the alveoli and facilitate gas exchange.

Respiratory Membrane

A very thin membrane across which gases must diffuse during gas exchange.

Type I Alveolar Cells

Simple squamous cells that line the alveoli and provide a surface for gas exchange.

Type II Alveolar Cells

Cells that produce surfactant to reduce surface tension in the alveoli.

Diffusion

The movement of gases from an area of high partial pressure to an area of lower partial pressure.

Partial Pressure

The pressure exerted by a specific gas in a mixture of gases.

Dalton's Law

States that in a mixture of gases, each gas exerts pressure in proportion to its abundance.

Atmospheric Pressure

The total pressure exerted by all gases in the atmosphere, approx. 760 mmHg.

Nitrogen

The most abundant gas in the atmosphere, accounting for about 78.6% of atmospheric pressure.

Oxygen

A gas essential for respiration, comprising about 20.9% of atmospheric pressure.

Carbon Dioxide (CO2)

A gas produced by cells during metabolism, making up about 0.04% of atmospheric pressure.

Gas Solubility

The ability of a gas to dissolve in liquid, influenced by pressure.

Respiratory Rate

The speed at which a person breathes, measured by the number of breaths per minute.

Respiratory Centers

Nerve centers in the brainstem that regulate the rhythm and depth of breathing.

Ventral Respiratory Group (VRG)

Medullary group that controls the basic rhythm of breathing.

Dorsal Respiratory Group (DRG)

Medullary group that controls inspiration and adjusts breathing depth.

Pneumotaxic Center

Located in the pons; regulates the rate and pattern of breathing.

High Pressure to Low Pressure

The principle by which gases move, e.g., oxygen moving from alveoli into blood.

Capillary Endothelium

Thin layer of cells lining blood vessels involved in gas exchange.

Simple Squamous Epithelium

A single layer of flat cells that facilitate diffusion; found in alveoli and capillaries.

Acidosis

A condition where blood pH decreases, prompting an increase in respiratory rate.

Alkalosis

A condition where blood pH increases, prompting a decrease in respiratory rate.

Chemoreceptors

Cells that monitor and respond to changes in blood chemistry, like pH and CO2.

Stretch Receptors

Receptors that inhibit over-inflation of the lungs during inhalation.

Cough Reflex

An involuntary response to clear the airway of irritants.

Sneeze Reflex

An involuntary response to clear the nasal passages of irritants.

Internal Respiration

The exchange of gases between the blood and body tissues.

External Respiration

The exchange of gases between the lungs and blood.

Interstitial Fluid

Fluid between cells that facilitates gas exchange with blood.

Oxygen Diffusion

The process by which oxygen moves from alveolar air to blood.

CO2 Diffusion

The process by which carbon dioxide moves from blood to alveolar air.

Bronchial Constriction

Narrowing of the air passages in response to low oxygen or high CO2.

Blood Flow Coordination

The regulation of blood flow to match airflow in the lungs.

Gas Exchange Efficiency

Determined by partial pressure differences, short distances, surface area, and blood/air flow coordination.

High Altitude Effects

Decreased oxygen levels due to lower atmospheric pressure at high altitudes.

Exercise Effects on Respiration

Increased rate and depth of breathing in response to metabolic demands.

Surface Area of Alveoli

The large total area provided by numerous alveoli for effective gas exchange.

Lung Compliance

The ability of the lungs to expand during inhalation.

Respiratory Alkalosis

A condition caused by hyperventilation, leading to increased blood pH.

Cardiovascular System's Role

Pumps oxygenated blood from lungs to body tissues.

Surfactant

Substance produced by type II alveolar cells to reduce surface tension in alveoli.

Respiratory Membrane Thickness

The minimal thickness required to facilitate rapid gas exchange.

Blood Oxygenation

The process of oxygen entering the bloodstream from the alveoli.

Respiratory Rates in Disease

Respiratory response can vary depending on individual pulmonary health.

Inhalation Mechanics

The primary muscles involved are the diaphragm and external intercostals.