Blood is fundamental to the tree of life, and there are different colors of it, ranging from green to purple to blue and even clear. Not forgetting that we also have our blood, which is red. The average human is made up of around 10 pints of blood, and our blood is not the same. All bloods are not created equal, so why is this?
Without blood, we cannot do a lot, including cooling off our bodies, being human at all, peeing, sweating, and performing other metabolic activities. Humans have red blood when we see it physically and that's what we all would agree on but have you heard someone saying blood can turn blue when it isn't carrying oxygen? In reality, blood doesn't change its color from red but people see blue when looking at veins because blue light reaches the surface of the skin better than red light.
In our body, blood moves through vessels which are known as Arteries and Veins, and these vessels branch into smaller ones known as capillaries until they can reach the smallest part of our body. The entire movement of blood in the body forms a close system that is moved from the heart to the lungs for oxygenation, then back to the heart to be pumped back to the body which uses up the oxygen and the nutrients there after which it is returned to the heart to be pumped back to the lungs.
Half of the blood is made of plasma which is made up of proteins, fat, salt, and water, Another thing that makes up our blood are platelets which are blood cells that help prevent us from bleeding to death. Red blood cell is another thing that makes up our blood. It makes up about 40 to 45% of our blood. The average individual can have up to 30 trillion red blood cells and their job is to carry oxygen from the lungs to the body and carbon dioxide out of the body, thanks to hemoglobin.
The color of our blood being red is thanks to Iron and it is what makes it taste metallic. The body makes about 2 million red blood cells every second with old blood cells constantly being replaced by new ones. Red blood cells are created in the bone marrow and as they develop into mature red blood cells, they lose their nucleus and this is a good thing as it allows them to squeeze through the tiniest vessel in the body. Their lack of a nucleus means they are not living and as such cannot repair damage or make more of themselves if they want to causing them to die after 4 months. The final component of our blood is the white blood cell which is interested in identifying self from non-self.
While our bloods perform the same function, it could be difficult for me to give you mine if you are in need of blood, and this is because of blood type. Scientists at some point in time were mixing different bloods together including those from animals, and during these dangerous tests of theirs, they noticed that some blood clot whenever they mixed them in a process known as Agglutination.
Soon scientists realized that our bloods could be categorized into three types and this was the beginning of the ABO system of categorizing and we know that mixing A and B do not always go well also mixing the plasma of O with any of the other two does not also always go well but mixing the blood from O to any of the plasma from the other two goes pretty well. This is because our immune system is always checking for foreign bodies and when it sees blood cell antigens that aren't part of the body, it begins to fight.
Aside from the ABO antigens, we know today that there are over 100 blood antigens but this is the common type today. Blood group A has the A antigens in its red blood cell and anti-B antibodies in its plama, Blood group B has the B antigens in its blood and anti-A antibodies in its plasma. A and B blood can be mixed together without them clashing. The O blood do not have anti-A or anti-B antigens and so when mixed with another blood they do not trigger a reaction because they do not have any antigens. This is why O is the universal red blood cell donor but the O plasma has anti-A and B antibodies which means there will be a reaction if they come in contact with any other red blood cell type.
When it comes to universal plasma donor, it is AB blood type, and when it comes to universal blood acceptors, it is still AB blood type. When plasma from one blood type is mixed with red blood cell from another type, it can lead to clumping as the immune cells in the plasma sees the antigen in the red blood cell as foreign.
The Rhesus factor is another way to categorize blood looking at the protein they carry. If the blood carries the protein, then it is positive but if it doesn’t, then it is negative. With combination of ABO and the Rh system, we have 8 blood type, bjt there are over 30 types of blood classification system. A very few people abiut 1 in 1 million people have the Bombay phenotype and these people do not have any if the blood type in the ABO system. These people will stay alive provided they do not get blood from anyone that has the ABO antigen. Some other set of people have the Rh-null type of blood which does not have any of the antigens in the Rh system but these people are so rare.
For now, scientists are still trying to understand why we have these blood types even though we have them. They can be a life-saver when a person in need of blood gets the right type of blood, and can be a murder weapon if the wrong type of blood is transfused. So you should check your blood type today.
https://www.nhs.uk/tests-and-treatments/blood-groups/
https://www.ncbi.nlm.nih.gov/books/NBK2267/
https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/blood-groups
https://www.blood.co.uk/why-give-blood/blood-types/
https://www.redcrossblood.org/local-homepage/news/article/what-is-the-rh-factor--why-is-it-important-.html
https://www.ncbi.nlm.nih.gov/books/NBK2269/
https://pmc.ncbi.nlm.nih.gov/articles/PMC10586525/
https://www.ncbi.nlm.nih.gov/books/NBK2268/
https://ourbloodinstitute.org/blood-matters/rhnull-rarest-blood-type/
https://rarediseases.info.nih.gov/diseases/12916/rh-deficiency-syndrome
