Blood is a connective tissue composed of multiple elements such as water, salt, sugar, fat, and proteins.
It comprises hemoglobin which is responsible for carrying oxygen to all the tissues of the body and gives the characteristic red color to the blood.
The fluid part of blood is known as plasma.
About 55% of blood is plasma and the rest 45% is red blood cells and other proteins.
It also comprises platelets (responsible for clotting) and white blood cells (help in fighting foreign infection).
Plasma is a pale yellow liquid comprising 90% water.
Plasma helps to transport blood cells throughout your body along with nutrients, waste products, antibodies, clotting proteins, chemical messengers such as hormones, and proteins that help maintain the body's fluid balance.
Final answer: The fluid part of the blood is called plasma.