What color is blood -- inside your body ? ?

Question

What color is blood -- inside your body ? ?

Answer 1

Blood is NEVER blue. This is a pet peeve of mine. A LOT of people think this for some reason but it always appears red.

Blood is composed of a few things:

-Red blood cells (erythrocytes)

-White blood cells

-Platelets

-Plasma (what everything "floats" in; plasma is mainly water)

-Plasma proteins (e.g. albumin)

In comparison to the other material in the blood plasma, red blood cells are the most plentiful. A single drop of blood contains millions of red blood cells.

Each red blood cell is composed of millions of haemoglobin molecules (~300million per RBC) and at the center of each haemoglobin is an atom of iron. This is why red blood cells appear red.

Heamoglobon is the pigment which binds oxygen for transport throughout the body. When oxygen is bound the RBC appears light red in color. When oxygen is not bound it (and is replaced by carbon dioxide) it appears a darker shade of red, almost a burgundy color . But at no point is the blood blue.

But the fact is that the blood's color is not the main contributing factor to the reason we see blue veins.

ANSWER:

To answer this question you have to first understand how we see anything at all. When we look at something, pigments in the object we are looking at absorb some of the colors while reflecting others. The colors that are not absorbed, but instead reflected back to our eye, is the color we see.

In order for us to see any color at all of our veins, even if it was green yellow purple red blue or what have you, the light first has to reach the vein itself. To do that it has to pass though the skin, hit the vein then pass back though the skin and into our eye. Now, I'm sure most of you would agree that our skin has color pigments; that it is not transparent but rather translucent. Because of these pigments light is not only absorbed when hitting the vein, but also when entering/leaving the skin. I guess in a way you could think of it this way: your skin over your blood vessel acts like a piece of colored plastic, the kind you might find in 3D glasses. Lets say you take out the blue plastic from 3D glasses and look though it. When looking through the plastic things you KNOW aren't blue appear to be blue. You skin acts very similar to this; light passing though the skin is absorbed and only the higher intensity wavelengths make it to your eye. These high intensity wavelengths of light are what our eyes interpret as 'blue'.

Some of you may be thinking now "Well if this is all true, why doesn't all the skin look blue?" You'll notice that the places that you see blue veins are in areas where the skin is thin and the blood vessel underneath is pushing up on it stretching the skin over it. Light hitting the dark color of the vein underneath the skin, in combination with the skin itself is what causes it to appear blue in these areas.

In short, it is not your vein that is blue but rather it is your skin with the shallow dark vessel underneath.

-Note- Some invertebrates do have blue "blood" but this is because they lack the chemistry we have making up our blood, specifically Iron-centered heamoglobin molecules of the red blood cells.

I realize this was a huge post, but it needed to be said. If you read all the way though it, props to you!

Answer 2

Venous blood (except in the pulmonary veins) is low in oxygen so the hemoglobin makes the blood have a dark red color.  Once the blood has passed through the capillary beds of the lungs, the blood will be bright red with the hemoglobin saturated with oxygen gas.

In First Aid classes they teach the caregiver to look for the color of the blood that is coming from an injury.  Bright red blood under pressure indicates an artery has been injured.  Dark red blood oozing out indicates a vein has been injured.

Answer 3

A dark red, almost burgundy

Answer 4

The color of blood depends on a few issues.

First, a majority of the blood is plasma and plasma is a straw / yellowish color.  Suspended in the plasma is a huge number of red blood cells (RBC).  When RBC are exposed to oxygen, they become red which, when suspended in the plasma, covers the yellow color.  When RBC have lost their oxygen, they become a purplish color which also covers the straw color of the plasma.  

So, you'll have to chose which situation most appropriately answers your question.

Answer 5

i think red

Answer 6

its red

Answer 7

Deoxygenated blood is still dark blue, regardless of what color the blood vessels are. The carbon dioxide and other wastes that the cells turn the cells this color. Oxygentated blood essentially is Oxygen attracted to the Iron atom in the center of hemoglobin. Essentially, rust is what makes your blood cells red!!

If you do not believe, cut your finger ::):P):)))

[I am kidding....]]