Human Physiology: Blood and O2 Transport

Flashcards covering gas exchange, blood components, O2 and CO2 transport, and factors affecting O2 unloading.

What is Boyle's Law?

Pressure is inversely related to volume.

According to Dalton's Law, what equals the total pressure?

The sum of the partial pressures of the individual gases.

What does Henry's Law state about gas in contact with a liquid?

Each gas dissolves in the liquid in proportion to its partial pressure and solubility until equilibrium is achieved.

What is Fick's Law of Diffusion?

The rate of gas transfer is proportional to the tissue area, the diffusion coefficient of the gas, and the difference in partial pressure of the gas on the two sides of the tissue, and inversely proportional to the thickness.

What is the approximate diameter of capillaries?

7-10 µm

What is the blood velocity in arteries?

34 cm•s-1

What is the blood velocity in capillaries?

0.05 cm•s-1

What percentage of blood is plasma?

Approximately 55%

What are the normal hematocrit percentages for females?

37-47%

What are the normal hematocrit percentages for males?

42-52%

What percentage of O2 is dissolved in plasma?

About 1%

What percentage of O2 combines with haemoglobin?

About 99%

Why is the biconcave shape of red blood cells important?

It increases the surface area, which increases the rate of diffusion.

What factors affect hemoglobin O2 affinity?

Acidity, partial pressure of carbon dioxide (Pco2), 2,3-Bisphosphoglyceric acid, Temperature

What happens to Hb affinity during acidosis?

Acidity increases/ pH decreases which causes Affinity of Hb decrease

What happens to Hb affinity during exercise?

Affinity of Hb decrease

What happens to Hb affinity with temperature increases?

Affinity of Hb decrease, More O2 is delivered to warmed up muscle

Where is myoglobin located, and what is its function?

Skeletal and cardiac muscle, transfering O2 from cell membrane to mitochondria/muscles

What happens when increased O2 demand happens?

Increased O2 demand = increased unloading, RBCs release ATP and NO, O2 sensors to increase blood flow, Stimulates vasodilation, Inhibits vasoconstriction

What does EPO(Erythropoietin) hormone do?

Stimulates RBC production in marrow of long bones

What are the CO2 transport methods?

Dissolved CO2 (~7%), Carbamino compounds (~23%), Bicarbonate ions (~70%)

What are consequences of decreased O@ carrying capacity?

Conditions like Hypobaric Environment and Anaemia

What is hypoxaemia?

Low O2 levels