Blood

Blood delivers necessary MATERIALS such as:

oxygen
nutrients
transports metabolic waste products away from those same cells

ERYTHROCYTES or RED BLOOD CELLS (RBC's)

Red blood cells develop in your body's spongy bone tissue (bone marrow) and is released into your bloodstream after about seven days
They typically live for about 120 days, and then they die
Red blood cells don't have a nucleus
Red blood cells contain a protein called hemoglobin (HGB), which is responsible for carrying oxygen
A single RBC has approximately 250 million molecules of hemoglobin protein
Each HGB can carry 4 O2 molecules

What is a normal red blood cell count?

Adult humans have somewhere around 25 trillion RBC's in their body.

Women usually have fewer than men, while people living at higher altitudes will usually have more.

*Red blood cells can squeeze through the capillaries one at a time

Men: 4.7 to 6.1 million red blood cells per microliter of blood
Women: 4.2 to 5.4 million red blood cells per microliter of blood
Children: 4.0 to 5.5 million red blood cells per microliter of blood

Red blood cells comprise approximately 70% of total human body cell number

BLOOD FLOW DURING EXERCISE

Other Components of Blood:

Plasma

Plasma accounts for around 55% of blood fluid in humans. Plasma is 92% water, and the contents of the remaining 8% include:

glucose
hormones
proteins
mineral salts
fats
vitamins

The remaining 45% of blood mainly consists of red and white blood cells and platelets. Each of these has a vital role to play in keeping the blood functioning effectively.

White blood cells, or leukocytes

White blood cells make up less than 1% of blood content, forming vital defenses against disease and infection. The number of white blood cells in a microliter of blood usually ranges from 3,700-10,500. Higher or lower levels of white blood cells can indicate disease.

Platelets, or thrombocytes

Platelets interact with clotting proteins to prevent or stop bleeding. There should be between 150,000 and 400,000 platelets per microliter of blood.

Bone marrow produces red blood cells, white blood cells, and platelets, and from there they enter the bloodstream. Plasma is mostly water that is absorbed from ingested food and fluid by the intestines. The heart pumps them around the body as blood by way of the blood vessels.

Medically reviewed by Meredith Goodwin, MD, FAAFP - Written by Adam Felman - Updated on July 13, 2021-https://www.medicalnewstoday.com/articles/196001#structure