Blood
Unlike mammals, horseshoe crabs do not have hemoglobin in their blood, but instead use hemocyanin to carry oxygen. Because of the copper present in hemocyanin, their blood is blue. Their blood contains amebocytes, which play a role similar to white blood cells for vertebrates in defending the organism against pathogens. Amebocytes from the blood of L. polyphemus are used to make Limulus amebocyte lysate, which is used for the detection of bacterial endotoxins.
Harvesting horseshoe crab blood involves collecting and bleeding the animals, and then releasing them back into the sea. Most of the animals survive the process; mortality is correlated with both the amount of blood extracted from an individual animal, and the stress experienced during handling and transportation. Estimates of mortality rates following blood harvesting vary from 3% to 15%.
Read more about this topic: Horseshoe Crab
Famous quotes containing the word blood:
“My great religion is a belief in the blood, the flesh, as being wiser than the intellect. We can go wrong in our minds. But what our blood feels and believes and says, is always true. The intellect is only a bit and a bridle.”
—D.H. (David Herbert)
“I have a blood bolt
and I have made it mine.
With this man I take in hand
his destiny and with this gun
I take in hand the newspapers and
with my heat I will take him.”
—Anne Sexton (1928–1974)
“See, see where Christ’s blood streams in the firmament!
One drop would save my soul—half a drop! ah, my Christ!—
Ah, rend not my heart for naming of my Christ!—
Yet will I call on him!—O, spare me, Lucifer!—
Where is it now? ‘T is gone; and see where God
Stretcheth out his arm, and bends his ireful brows!—
Mountains and hills, come, come and fall on me,
And hide me from the heavy wrath of God!”
—Christopher Marlowe (1564–1593)