How Does Heoglobin Affect The Variation Of Oxygen?
module 3 ematology – Module 3, Lecture 1
Slide 1
● The first type of blood cells that we will focus on are the erythrocytes, also called the red blood cells. These are the cells that transport oxygen in the blood from the lungs to the tissues. These cells also help transport some of the carbon dioxide from the tissues to the lungs. The main function of erythrocytes, namely oxygen transport, is carried out by the protein that makes up the majority of the protein composition of the cell, hemoglobin. We will also be looking at how hemoglobin delivers oxygen, and how many factors affect its affinity for oxygen. Lastly we will be looking at some variations of hemoglobin, one variation of which is determined by the combination of chains, and which occurs …show more content…
It shows the relationship between the partial pressure of oxygen and the percent saturation of hemoglobin by oxygen.
Partial pressure of oxygen is the pressure it exerts in a mixture of gases, and is proportional to its concentration. The S shape, or sigmoid shape, of the curve reflects the fact that more than one oxygen can bind to hemoglobin, and that binding of oxygen facilitates binding of the same hemoglobin molecule to other oxygen molecules.
● Let’s focus on the red curve because this is the dissociation curve under normal conditions. We can look at this curve starting from the top right position of the graph.
Notice that the plateau is quite long before it starts to descend. This means that over a wide range of partial pressures of oxygen, the percent saturation of hemoglobin remains high at 90% or greater. This provides an excess capacity for oxygen delivery especially when oxygen availability becomes low. At partial pressures of oxygen in tissues, which usually average around 40 mm Hg, more than 50% of hemoglobin is still saturated. So oxygen is released at physiological partial pressures, but it is not readily given off by
Slide 1
● The first type of blood cells that we will focus on are the erythrocytes, also called the red blood cells. These are the cells that transport oxygen in the blood from the lungs to the tissues. These cells also help transport some of the carbon dioxide from the tissues to the lungs. The main function of erythrocytes, namely oxygen transport, is carried out by the protein that makes up the majority of the protein composition of the cell, hemoglobin. We will also be looking at how hemoglobin delivers oxygen, and how many factors affect its affinity for oxygen. Lastly we will be looking at some variations of hemoglobin, one variation of which is determined by the combination of chains, and which occurs …show more content…
It shows the relationship between the partial pressure of oxygen and the percent saturation of hemoglobin by oxygen.
Partial pressure of oxygen is the pressure it exerts in a mixture of gases, and is proportional to its concentration. The S shape, or sigmoid shape, of the curve reflects the fact that more than one oxygen can bind to hemoglobin, and that binding of oxygen facilitates binding of the same hemoglobin molecule to other oxygen molecules.
● Let’s focus on the red curve because this is the dissociation curve under normal conditions. We can look at this curve starting from the top right position of the graph.
Notice that the plateau is quite long before it starts to descend. This means that over a wide range of partial pressures of oxygen, the percent saturation of hemoglobin remains high at 90% or greater. This provides an excess capacity for oxygen delivery especially when oxygen availability becomes low. At partial pressures of oxygen in tissues, which usually average around 40 mm Hg, more than 50% of hemoglobin is still saturated. So oxygen is released at physiological partial pressures, but it is not readily given off by