what makes up 55 percent of blood

About 55 percent of blood is made up of plasma , the liquid portion that carries cells and dissolved substances.

Quick Scoop

Plasma is mostly water (about 90–92%) and serves as the fluid medium that allows blood cells to move through blood vessels. It also helps maintain blood volume and pressure so organs get enough circulation.

What plasma contains

Within that 55 percent plasma fraction, the key components include:

• Water (the majority, around 90–92%)
• Proteins such as albumin, antibodies, and clotting factors
• Glucose (sugar) for energy
• Mineral salts and electrolytes (like sodium and potassium)
• Hormones, vitamins, fats, and other nutrients and waste products

These dissolved substances are what let blood deliver nutrients, remove waste, transport hormones, and support immunity.

In short, when asking “what makes up 55 percent of blood,” the answer is the watery plasma that carries everything else.

Information gathered from public forums or data available on the internet and portrayed here.