Question #c128c

1 Answer
Nov 26, 2017

About 56% of the total blood volume is made of the plasma.

Explanation:

In this drawing
~ About 56% of the total blood volume is made of the plasma.

~ Red blood cells at the bottom take up about 42%.

~ White blood cells and platelets (the thin middle layer) take up about 2%
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You can estimate those percents by looking at the marks on the side
of the test tube.
The top plasma portion takes up about 5.6 ml out of the total
of 10 ml. That is 56% of the total.
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When whole blood is spun in a centrifuge, the heaviest component is forced to the bottom of the tube.
The heaviest part of a blood sample is the portion made of red blood cells.

Normally, women's blood is about 34.9% to 44.5% red blood cells.
Normally, the blood of males is between 38.8% to 50% RBCs.
https://www.mayoclinic.org/tests-procedures/hematocrit/details/results/rsc-20205482

In the blood sample you posted, the red blood cells take up about 42% of the total volume of the blood -- completely within normal range.

The rest of the tube is filled with the liquid plasma and the small number of white blood cells.
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Centrifuging the blood to find the volume taken up by red blood cells is a test called the hematocrit.
It is used to check for anemia and other conditions.

Here is an image first showing on the left a tube of blood as it looks right after it has been taken from the patient.
enter image source here
The next tube shows a normal level of RBCs.
To the right of the normal sample, there are pictures of crits from blood with too few RBCs and from blood with too many RBCs.
http://the-healthcare.org/symptoms-and-diagnosis/lab-results/high-and-low-hematocrit-levels/