The CEA test measures the level of carcinoembryonic antigen (CEA) in the blood.CEA is a protein normally found in the tissue of a developing baby in the womb. The blood level of this protein disappears or becomes very low after birth.he CEA test measures the level of carcinoembryonic antigen (CEA) in the blood.
Blood is made up of cells in a watery base, called plasma. There are three major types of cells blood made up of â red blood cells (RBCs), while blood cells (WBCs) and platelets. 1  They are also known as erythrocytes, carry oxygen to various parts of the body.  They are the most in number, constituting about 40-45% of blood. Their structure is like that of dough nuts.
In a nutshell, below are some few facts about the amount of blood in human body: 1. The amount of blood in a human body depends on age, sex, overall health and even where people reside. 2. Blood makes up roughly 7 percent of the weight of a human body. 3. Water makes up 90 per cent of blood plasma. Blood plasma also contains various electrolytes, glucose, gases, nutrients, proteins, and hormones.