Final answer:
Anemia is a condition marked by a deficiency in red blood cells or hemoglobin, leading to reduced oxygen delivery to the body's cells. Causes of anemia range from bleeding to inherited disorders or nutritional deficiencies, with various types impacting health differently.
Step-by-step explanation:
The condition in which a person has an abnormally low number of red blood cells (RBCs) or hemoglobin is known as anemia. Anemia impairs the blood's ability to carry oxygen to the cells, which can lead to symptoms such as weakness and fatigue. There are various types of anemia, which can be caused by factors such as excessive bleeding, inherited disorders (like sickle cell anemia), or nutritional deficiencies (including iron, folate, or vitamin B12 deficiencies). Conditions such as aplastic anemia and thalassemia involve diminished RBC production or abnormal RBC maturation, while sickle cell anemia is characterized by abnormally shaped hemoglobin that impedes blood flow and oxygen delivery.