Fish Blood, Blue Blood | God's World News

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Fish Blood, Blue Blood
Science Soup
Posted: November 01, 2023
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    Zebrafish blood is similar to human blood. (AP/Steven Senne)
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    This image shows the early stages of a zebrafish embryo’s development. The embryo is see-through. That makes it easy for scientists to study. (Ed Hendel/CC BY-SA 4.0)
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    The horseshoe crab is not actually a crustacean. It is a different type of arthropod. (123RF)
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    Horseshoe crabs have blue blood. (AP)
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    Gulls and other species need horseshoe crabs for food. (AP/Matt Rourke)
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Fish Blood!

The striped zebrafish looks like its namesake. It doesn’t look like a human . . . until you study its blood.

Blood has a big job. Red blood cells carry oxygen through the body. (Even fish need oxygen! They absorb it from water through gills.) White blood cells help fight infections.

Zebrafish blood is similar to human blood. That makes the fish a good scientific model. Researchers study zebrafish blood to learn how human blood forms.

Lookalike blood isn’t the only helpful trait of these swimmers. Zebrafish grow quickly. One day of zebrafish development is like three months of human development! In early stages, researchers can see into the translucent zebrafish. They watch cells form.

Blood cells start out as stem cells. Stem cells can develop into all types of body cells. Some of those help fight blood disorders. If scientists learn how stem cells grow, they may learn to battle diseases.

Blue Blood!

It’s blue, but don’t drink it. It only looks like Gatorade!

This is horseshoe crab blood. Scientists extract from it a chemical that is used to test many medicines.

Is the medicine carrying dangerous germs? If so, the crabby chemical will detect it.

But it comes at a cost. Workers at medicine companies “bleed” horseshoe crabs. Some crabs don’t survive the process.

That causes even more trouble. Species like the red knot bird need horseshoe crab eggs for food. Officials list horseshoe crabs as a “vulnerable species.” They say, “No more harvesting for a while. Crabs need a break to reproduce.”

God designed animal blood to do remarkable work. Could we someday do this work without the crabs? Researchers look for a man-made substitute.

For now, we don’t have other options. We can give thanks for God’s provision.

Why? God mercifully provides animal blood to help with people’s medical needs.