Four Blood Groups: A, B, AB, and O
When you are born, you will be given lettered blood type such as A, B, AB, or O. These blood types are determined by which antigens are found on your red blood cells and which antibodies are in your plasma. Antigens are the substances that control what enters and exits a cell and activate an immune response. Antibodies are the blood proteins. Each of these lettered blood types can be either negative or positive, and this means that instead of only four lettered blood types, we have a total of eight lettered blood types. If you have a positive (+) or a negative (-) part in your blood type, this is usually determined by the presence (+) or the absence (-) of the third antigen in your blood type known as the Rh factor.
23 Pairs of Chromosomes in Our Bodies
In our bodies, there are pairs of chromosomes. Each of these cells contains all genetic material that. The makeup of our entire bodies is determined by these sets of chromosomes. That is also the reason why it is possible to clone animals with only one cell. From our toenails to follicles, all of these are defined by each and every cell in our body.
Experts Are Still Unsure Why Humans Yawn
As we all already know, experts claim that by yawning, humans are able to keep their brains active and alert at all times. However, what we do not know is that no one knows exactly how yawning helps our body. If you pay enough attention, when one person is yawning, another person who is close by will copy the action and yawn too. Scientists believe that yawning is contagious and that another person's action of yawning will alert us. Other people claim that yawning is our brain's way of telling us that our body is tired and it needs more oxygen. However, even scientists are still not 100% sure how yawning help in human biology.
These are only 3 fascinating facts about human biology. We will try to cover up more topics and facts about human biology in the next posts!
