Hemoglobin

This lesson will look at hemoglobin by examining:

1. Structure and Function
2. Oxyhemoglobin

1. Structure and Function

Hemoglobin is a protein containing iron that's found within red blood cells and binds to oxygen. It is an important component of red blood cells because it what allows blood to carry oxygen to the cells and tissues of the body. Oxyhemoglobin is the name that we give to hemoglobin that is carrying oxygen.

• Hemoglobin
• A quaternary pigment protein found on red blood cells, hemoglobin is primarily used to transport oxygen and some carbon dioxide throughout the blood.
• Oxyhemoglobin
• The term used to describe when oxygen is bound to hemoglobin; oxygen + hemoglobin = oxyhemoglobin.
• Iron
• The actual iron atom within the heme group to which oxygen binds.

One molecule of hemoglobin can bind up to four oxygen molecules at a time, but factors such as the ratio of carbon dioxide to oxygen in the blood, temperature, and acidity of the tissues can affect this amount of oxygen that binds to hemoglobin.

There are two parts to a hemoglobin molecule:

• Globin- a protein, is made up of four linked polypeptide chains. These polypeptide chains are associated with a heme group.
• Heme group-the part of hemoglobin that contains iron.

Iron is found in the middle of the heme group, and the iron is what binds to oxygen.

• Globin
• A term used to describe the protein structure of hemoglobin.
• Heme Group
• This is the iron group in the center of each globular protein in a hemoglobin molecule; therefore one hemoglobin molecule has four heme groups associated to it. The heme group is what oxygen binds to when red blood cells are circulating oxygen throughout the body.

2.Oxyhemoglobin

Hemoglobin can bind up to four oxygen molecules because the four heme groups, each containing iron in the middle. Oxyhemoglobin, or hemoglobin when it is carrying oxygen, gives blood a deep red color. because when the iron in these heme groups binds to the oxygen, it produces that deep red color.

Did you know that when iron is exposed to oxygen, it produces rust? The process of that reaction happening gives blood that deep red color when the iron in the heme group binds with oxygen.

When hemoglobin is lacking oxygen, the blood appears to be more of like a purplish, bluish color as it travels through your veins.

The structure of hemoglobin comprises two parts: globin and a heme group. The heme group contains iron in the middle of it which can bind with oxygen. Hemoglobin is a component of the red blood cell. The function of hemoglobin is to carry oxygen in the blood to the cells and tissue of the body. Oxyhemoglobin is a hemoglobin molecule carrying oxygen. Because of the reaction between iron and oxygen in Oxyhemoglobin, blood has a deep red color.

Keep up the learning, and have a great day!