Dictionary > Hemoglobin

Hemoglobin

Definition
noun, plural: hemoglobins
A biomolecule made up of haeme (i.e. oxygen-carrying, nonprotein, ferrous component) and globin in red blood cells
Supplement
Red blood cells or erythrocytes take up oxygen through the respiratory circuit and deliver the oxygen to the tissues via the circulatory system. The erythrocytes of vertebrates are rich in hemoglobin. Hemoglobin is an iron-containing biomolecule. It is made up of four haem (or heme) groups and globin. The haem groups contain iron atoms that can bind reversibly to oxygen molecules. There are four globin polypeptide chains, designated as alpha, beta, gamma, and delta, respectively, in the adult. Each is composed of several hundred amino acids. A hemoprotein composed of globin and heme that gives red blood cells their characteristic color. Thus, the primary function of hemoglobin is to bind to oxygen molecules in the respiratory organs such as lungs and gills, and then transport oxygen to tissues. Apart from oxygen, the hemoglobin can also bind to and carry waste product, i.e. carbon dioxide, from tissues. In adult humans, the erythrocytes lack a nucleus and other organelles in order to maximize space for hemoglobin.
Word origin: Greek haƮma (blood) + Latin globus (ball, sphere) + -in
Abbreviation / Acronym: Hb or Hgb
Variant(s):

  • haemoglobin (British)

See also:

  • heme
  • blood
  • erythrocyte
  • Related term(s):


    You will also like...

    Salmon jumping upstream in the river
    Lotic Communities & Animals

    A running water environment offers numerous microhabitats for many types of animals. Similar to plants, animals in lotic..

    green plant cells
    Plant Cells vs. Animal Cells

    Plant cells have plastids essential in photosynthesis. They also have an additional layer called cell wall on their cell..

    Types and Causes of Brain Damage
    Types and Causes of Brain Damage

    This tutorial describes the different types and causes of brain damage. Find out how genetics, physical injury, lack of ..

    Consciousness and behavior
    Consciousness and Behavior

    Human consciousness and behavior are an interesting topic since they are determined and controlled by the brain. Conscio..

    Control of body movement
    Control of Body Movement

    Some of the body movements can be controlled at will, others cannot. The body has a motor program, which is the pattern ..

    Circulation
    Circulation

    The circulatory system is key to the transport of vital biomolecules and nutrients throughout the body. Learn about the ..