Final answer:
The term 'hist/o' is related to tissues and histology, not blood vessels. Blood vessels develop from the embryonic mesoderm and are crucial for the cardiovascular system function. Hematopoiesis in bone marrow produces the cells that circulate in the blood.
Step-by-step explanation:
The combining form hist/o does not refer to blood vessels; instead, it reflects a connection to tissues, as seen in the study of histology, which is the study of the shape and arrangement of cells in tissue. The blood vessels are hollow, tube-like structures that include veins, arteries, and capillaries, and they are vital for cardiovascular system function. They begin to form from the embryonic mesoderm with precursor hemangioblasts differentiating into angioblasts, which contribute to the formation of blood vessels, as well as pluripotent stem cells which differentiate into the various formed elements of the blood. This development is essential as blood vessels mature to efficiently transport blood, delivering oxygen and nutrients to cells, and removing metabolic waste.
Blood is a connective tissue due to the process of hematopoiesis, which occurs in the red marrow of bones. The blood hydrostatic pressure is the force that blood exerts against the walls of a blood vessel or heart chamber. The concept of blood islands refers to masses of developing blood vessels and formed elements from mesodermal cells scattered throughout the embryonic disc.