Gas Diffusion, gas Transport and haemoglobin 1 & 2

These flashcards cover key vocabulary terms and concepts related to gas diffusion and transport, aiding in the understanding of respiratory physiology.

Gas Diffusion

The process by which gas molecules spread or move from an area of higher concentration to an area of lower concentration.

Alveolus

The small air sacs in the lungs where gas exchange occurs.

Pulmonary Vein

Blood vessels that carry oxygenated blood from the lungs to the heart.

Pulmonary Artery

Blood vessels that carry deoxygenated blood from the heart to the lungs.

Terminal Bronchiole

The last division of the bronchi before air reaches the alveoli.

Respiratory Bronchiole

The bronchioles that lead directly to the alveoli, involved in gas exchange.

Diffusion Constant (D)

A specific value for a gas that describes how easily it diffuses.

Fick’s Law

A law stating that the rate of gas diffusion is proportional to the surface area and the partial pressure difference.

Partial Pressure

The pressure exerted by a single type of gas in a mixture of gases.

Oxygen Saturation (SaO2)

The percentage of hemoglobin binding sites in the bloodstream occupied by oxygen.

Diffusion Capacity (DL)

A measure of the conductance of the alveolocapillary barrier for gases.

Bohr Effect

The physiological phenomenon where an increase in CO2 or a decrease in pH causes a decrease in oxygen affinity of hemoglobin.

2,3-DPG

2,3-diphosphoglycerate, a compound that decreases hemoglobin's affinity for oxygen.

Myoglobin

An oxygen-binding protein found in muscle tissue that has a higher affinity for oxygen than hemoglobin.

Hemoglobin

A protein in red blood cells that binds to oxygen and carries it throughout the body.

Arterial Oxygen Content (CaO2)

The total amount of oxygen carried in the arterial blood, calculated based on hemoglobin and dissolved oxygen.

Carbonic Anhydrase

An enzyme that catalyzes the conversion of carbon dioxide and water into bicarbonate and protons.

Haldane Effect

The phenomenon where deoxygenated hemoglobin has a greater affinity for CO2 than oxygen.

Alveolocapillary Barrier

The thin barrier separating the alveoli from the capillaries, facilitating gas exchange.

Myoglobin vs Hemoglobin

Myoglobin has a higher affinity for oxygen than hemoglobin and is designed for oxygen storage in muscles.

Venous Blood

Blood that returns to the heart after delivering oxygen and collecting carbon dioxide.

Erythrocytes

Red blood cells responsible for transporting oxygen and carbon dioxide in the blood.

Rightward Shift

A shift in the oxygen-hemoglobin dissociation curve, causing hemoglobin to release oxygen more easily.

Leftward Shift

A shift in the oxygen-hemoglobin dissociation curve, causing hemoglobin to hold onto oxygen more tightly.

Interstitial Space

The fluid-filled space surrounding cells in the tissues.

Capillary Endothelium

The inner lining of capillaries, involved in the exchange of gases and nutrients.

Oxygen Transport

The movement of oxygen from the lungs to the body's tissues via the bloodstream.

Strenuous Aerobic Exercise

Highly intensive physical activity that significantly increases oxygen demand in muscles.

Anemia

A condition characterized by a deficiency in the number of red blood cells, leading to reduced oxygen-carrying capacity.

Methemoglobin

A form of hemoglobin that has been oxidized and cannot bind oxygen effectively.

Chloride Shift

The process of exchanging bicarbonate ions and chloride ions across the red blood cell membrane.

Total Lung Capacity

The total volume of air that the lungs can hold.

Alveolar Oxygen Uptake

The process through which oxygen moves from the alveoli into the blood.

Diffusion Gradient

The difference in concentration of a gas across a membrane, driving diffusion.

Cardiac Output

The amount of blood the heart pumps in one minute; typically expressed in liters per minute.

Hypercapnia

An increased level of carbon dioxide in the blood.

Hypoxemia

A lower than normal level of oxygen in the blood.

Pulmonary Function Tests

A set of tests that measure how well the lungs are working.

Gas Exchange

The process by which oxygen is taken into the body and carbon dioxide is expelled.

Oxygen Availability

The presence of oxygen in sufficient quantities to meet the metabolic needs of tissue.

Physically Dissolved Oxygen

The portion of oxygen in blood that is not bound to hemoglobin and is dissolved in plasma.

CO2 Transport Mechanisms

The methods by which carbon dioxide is transported in the blood: dissolved, bound to hemoglobin, and as bicarbonate.

Surface Area for Diffusion

The area available in the alveoli for gas exchange, which affects the efficiency of diffusion.

Diffusion Rate

The speed at which gas moves across the alveolocapillary barrier.

Hypoxia

A condition characterized by insufficient levels of oxygen in the tissues.

Ventilation-Perfusion Ratio

The ratio of air reaching the alveoli to the amount of blood reaching the alveoli.

Fick’s Law of Diffusion

The principle that describes the relationship between diffusion and factors such as surface area and partial pressure difference.