A Brief Introduction
Itis useless to say that blood plays a number of very important rolesboth in humans and animals. Amongst its most important functionswould most definitely be carrying of oxygen in and out of the heart.
Butblood isn't only used for oxygen transport. It is also used totransport waste from the body to the excretory system, amongst otherthings.
Humanblood consists of of plasma (55%) and three types of cells (45%).Red, white and platelets. Plasma is, for its most part (about 90%)made up of water and various salts.
Apartfrom the mentioned, human blood also contains a number of a certaintype of proteins. These proteins are called antigens. And it is thepresence of these antigens that is the deciding factor of which bloodtype a person has. These blood types are commonly known as "bloodgroups", and this article takes a closer look at their differentproperties.
So what are bloodgroups?
Bloodgroups were first discovered by Karl Landsteiner (in 1901). Upondiscovery, he had classified human blood into four groups. The fourrelevant types of blood a person may have are: A, B, AB and O.
Thisclassification was based upon the presence of the above mentionedantigen in human blood. For instance, if the person's blood containedan antigen A, the particular person's group was was A, and so forth.
Aperson's blood group is normally determined at birth.
Nextoff, it should be noted that there is another factor which helpsclose pin down a particular person's blood group. This factor iscalled Rhesus (Rh). The presence of this factor is one thatdetermines whether a person's blood group is positive or negative.
Soaccordingly, if a person's blood contains antigen B, as well asRhesus factor D, his or her blood type shall be B+. Similarly, if thesame person's blood lacked but the Rhesus factor D, the blood groupwould be B-.
Andaccording to the above stated, human blood may be categorized intoeight groups, thus: A+, A-, B+, B-, AB+, AB-, O+, and O-.
Knowing one's blood group is an important bit of medical information, sinceno transfusion could be carried out otherwise. Nextly, the differencebetween the Rh factors of a baby's parents blood types could create anumber of threatening conditions for the child. Luckily, this littleissue could be overcome by means of use of modern medication.
So what is the mostcommon blood type?
Themost common blood types are the Rhesus factor positive ones. Namely,nearly 85% of the world's population is Rhesus factor positive. Andinside that group, it has been statistically proven that the mostfrequent group would be O+ (with about 35%-40% of the world'spopulation sharing it).
Thisblood group is also known as the universal donor, because a personwho's got it may donate blood to people with any other blood types.
Thesecond in line when it comes to popularity would be blood group A+.