A horseshoe crab has been around for almost 500 million years. They are classified as arthropods and not actual crabs. However, There are many reasons that have helped them survive this long including, they can eat almost any organic matter. There blood is different from normal, in fact it’s blue. This blood helps them heal any wounds right away. They can also live in areas with very low levels of oxygen, meaning habitat is not a big issue for them. Evolution has also helped them grow and adapt seeing as they’ve survived this long.
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Answer:
Sickle cell anemia is an inherited condition in which there aren't enough healthy red blood cells to carry oxygen through an individual's body. The red blood cells of a healthy individual are flexible and round, and they move through blood vessels with no problem, transporting oxygen successfully. However, a person with sickle cell anemia has rigid, sticky red blood shaped like sickles or crescent moons. These cells often get stuck in small blood vessels, which can slow or block blood flow and oxygen delivery to different parts of the body.
The sickle cell anemia trait is found on a recessive allele of the hemoglobin gene, while the regular red blood cell trait is found on the dominant allele. This means that a person must have two copies of the recessive allele (one from their mother and the other from their father) to be born with this condition. People who have one dominant and one recessive allele or both dominant alleles will have healthy red blood cells.
I think the answer is the moon in its orbit around the Earth
<span>Russell's case (two illnesses: bipolar disorder and substance use disorder) illustrates </span>comorbidity. The term comorbity is used in medicine to denote a presence of two diseases or disorders, one primary and one additional, both occurring at the same person.