What factor determines the rate of exchange of oxygen between the alveolus and blood capillaries?

The rate of gaseous exchange in alveoli and blood depends on the difference in pressure of gases in both the alveoli and blood capillaries. Explanation: The air in alveoli has high pressure of oxygen and low pressure of carbon-dioxide.

How does oxygen diffuse into tissues?

Oxygen transport within the human body occurs through both convection and diffusion. Oxygen diffuses from both the alveoli into the pulmonary capillaries and the systemic capillaries into the tissues, according to Fick’s laws of diffusion and the random walk of the diffusing particles.

How does oxygen pass from the blood to the mitochondria?

Red blood cells pass through capillaries in single file due to the similar size of RBCs and the capillary caliber. As RBCs flow through capillaries, oxygen is continuously released from the RBC hemoglobin and eventually diffuses to the mitochondria where it is consumed.

What happens to oxygen as it enters the blood capillary?

In the tiny capillaries of the body tissues, oxygen is freed from the hemoglobin and moves into the cells. Carbon dioxide, made by the cells as they do their work, moves out of the cells into the capillaries, where most of it dissolves in the plasma of the blood.

How does oxygen get from capillaries to cells?

The transfer of oxygen into the blood is through simple diffusion. The oxygen molecules move, by diffusion, out of the capillaries and into the body cells. While oxygen moves from the capillaries and into body cells, carbon dioxide moves from the cells into the capillaries.

How are gases exchange at alveolus and tissues with blood explain your answer by comparing the partial pressures at different parts?

The partial pressure of oxygen is high in the alveoli and low in the blood of the pulmonary capillaries. As a result, oxygen diffuses across the respiratory membrane from the alveoli into the blood. In contrast, the partial pressure of carbon dioxide is high in the pulmonary capillaries and low in the alveoli.

What factors affect alveolar gas exchange?

Fick’s law gives us a number of factors that affect the diffusion rate of a gas through fluid:

• The partial pressure difference across the diffusion barrier.
• The solubility of the gas.
• The cross-sectional area of the fluid.
• The distance molecules need to diffuse.
• The molecular weight of the gas.

Does oxygen diffuse in blood?

Oxygen diffuses through the cell membrane and is transported in blood plasma by free diffusion and by convection.

What does oxygen do for tissues?

Oxygen is vital for living cells; it plays a fundamental role in their metabolism. However, the simple molecular diffusion of gases in tissues, as well as nutrients is not sufficient for the metabolic needs of large, complex and active multicellular organisms.

Which gas passes into the blood from the alveoli?

Oxygen
Oxygen breathed in from the air passes through the alveoli and into the blood and travels to the tissues throughout the body. Carbon dioxide travels in the blood from the body’s tissues and passes through the alveoli to be breathed out.

What are the factors that influence tissue gas exchange?

The factors that influence tissue gas exchange are similar to the factors of alveolar gas exchange, and include partial pressure gradients between the blood and the tissues, the blood perfusion of those tissues, and the surface areas of those tissues.

How is oxygen and carbon dioxide transported in the blood?

Although gas exchange is a continuous process, the oxygen and carbon dioxide are transported by different mechanisms. Although oxygen dissolves in blood, only a small amount of oxygen is transported this way. Only 1.5 percent of oxygen in the blood is dissolved directly into the blood itself.

What percentage of oxygen in the blood is dissolved in blood?

Only 1.5 percent of oxygen in the blood is dissolved directly into the blood itself. Most oxygen—98.5 percent—is bound to a protein called hemoglobin and carried to the tissues. Hemoglobin, or Hb, is a protein molecule found in red blood cells (erythrocytes) made of four subunits: two alpha subunits and two beta subunits (Figure 20.19).

Why is carbon dioxide more soluble than oxygen in blood?

Although carbon dioxide is more soluble than oxygen in blood, both gases require a specialized transport system for the majority of the gas molecules to be moved between the lungs and other tissues. Even though oxygen is transported via the blood, you may recall that oxygen is not very soluble in liquids.