"Waste" -- in the form of urine and feces -- how the body removes the parts of food we ingest that is not used for nutrition and also is a way to rid the body of toxins. The kidneys filter the blood, removing "waste" products such as excess vitamins or drugs (this is why your urine can have a bright color if you take high doses of vitamin c) and liquid waste is held in the bladder before being released. Food travels through the gut to be digested -- broken down into usable bits and waste. After breaking down in the stomach, the material travels through the small and large intestines. The small intestine is lined with villi -- tiny protrusions that add surface area so nutrients can be absorbed into the bloodstream. In the large intestine and colon, water is pulled from the mass so it becomes more solid. Eventually the solidified waste passed through the rectum and out the anus as feces. The build-up of waste in the body can itself be toxic -- if the kidneys do not function properly to clean the waste out, the buildup can be fatal. When the body goes into emergency mode to eliminate a toxic substance -- such as e. Coli in the case of food poisoning -- the intestines don't both absorbing water and the result is the liquid fecal matter being quickly passed through and ejected as diarrhea.
This isn't always the case and there is no reason it should be .Whether or not a trait is common has to do with how many copies of that gene version (or allele) are in the population. It has little or nothing to do with whether the trait is dominant or recessive. Let's take eye color as an example.
Answer:
ABO blood grouping system is based on presence or absence of three types of antigen on red blood cells. A and B blood group have A and B antigens respectively. AB blood group has both A and B antigens. O blood group does not have any antigen.
A body with particular blood type will consider other blood group foreign ( because it has different antigen ) and produce antibodies against it. A person with blood type A can not be given B type blood because the antibodies in his body will destroy RBCs with B antigen which may even prove fatal.
AB blood type person can receive blood from both A and B blood groups because he has antigens for both of them so it will produce antibodies for neither of them. He can also receive O type blood because O blood does not have any antigen so it can be given to any person without incompatibility reaction.
However, AB individual can only donate blood to AB individual because his blood cells have both A and B antigens. So, he can only donate blood to an individual who does not produce antibodies for both A and B blood groups and that would only be another AB blood type individual.