Motorcycle rider with skull face paint

Photo courtesy of Depositphotos

I’m a big horror movie fan. Huge. I often stay up far too late watching movies of questionable cinematic quality long after my family has gone to bed. Last night as I was watching the latest offering from Netflix, right as the tension reached its peak, one of our cats, Joseph, knocked over a vase of roses and I nearly went into cardiac arrest. Joseph is even named after a character in a horror movie! (Bonus points if you can guess which movie.)

One common ingredient in many horror movies is blood. I have a particular pet peeve when they get blood wrong – F/X folks often use red-colored syrup, which is clear. Blood is not clear, my dear friends in the F/X department. It drives me to distraction and pulls me right out of the movie when I see trickles, splashes, or buckets of clear strawberry syrup in a horror movie. Sure, if I was indulging in Attack of the Very, Very Angry and Yet Also Quite Fluffy Killer Pancakes from Zondar, I might give them a pass, but I know blood and I know what it looks like. I’d be happy to consult on any horror film that needs a blood advisor.

So, why is blood not clear? Isn’t it just this red fluid that courses through our pets’ bodies and ours, merely dropping off oxygen here and there?

No. Just, no.

Blood is amazing. I know that word is overused these days (I mean, really, just how amazing can a muffin be?) but blood definitely deserves the title of amazing.

Let’s open up a vein and delve into just what makes blood so amazing.

1. Blood is not clear because it has stuff in it.

My little pet peeve about clear blood in movies arises because real, actual blood is not clear. It’s chock full of cells, fragments of cells, proteins and other good stuff. Red blood cells (RBCs - not to be confused with ROUSs – Rodents of Unusual Size) are donut-shaped little guys that are full of hemoglobin, an iron-containing compound that loves to hold on to oxygen, but doesn’t love it so much that it can’t be convinced to drop it off to your cells when they need it. It’s like going to the Piggly Wiggly (your lungs) to pick up some Yoo-Hoo (oxygen), but then running into a thirsty friend (your cells) on the way home and saying “Hey, thirsty friend, have some of my delicious Yoo-Hoo vaguely chocolate-flavored beverage.” Sorta.

2. If your blood turns from a liquid to a solid sometimes it saves your life, sometimes you die. 

Most of the time, blood is a liquid that courses through our bodies, dropping off oxygen here and there. To do that, it has to stay liquid to deliver it to all the trillions of cells and nooks and crannies that make Fido Fido and you you.

But what if Fido springs a leak? What if you’re Kevin Bacon and Freddy decides to hurt you in the neck with an arrow from under the bed? (Look it up.)

All of Fido’s blood would just leak out everywhere, maybe killing him and certainly leaving a big mess. Luckily for Fido and Kevin Bacon, your blood has the amazing ability to go from liquid to solid when the need arises. Take that, Freddy Krueger! (Incidentally, I once bought a glass of wine for the actor who plays Freddy Krueger, Robert Englund, and talked movies for an hour or so. He was very nice and hardly stabbed me at all.)

How blood goes from a crimson river of oxygen delivery to a jelly-like clot is…amazing. It’s a complicated dance of proteins and cells that even blood-ologists don’t fully understand. Basically, when Fido gets cut, proteins in the blood vessels that are normally kept under wraps are exposed and the blood says “Hey, lookee there. Someone’s lit up the Time to Clot sign!” and a blood clot forms and Fido’s neck stops leaking Kevin Bacon’s blood. Making a clot involves platelets, which are tiny chips of cells that are just loaded with substances that encourage blood to clot. When they see the Time to Clot sign (which is technically known as subendothelial collagen) they arrive on the scene of the cut and just sorta sploodge all their insides everywhere. All that platelet sploodge makes another protein in the blood (fibrinogen) turn from a liquid to strands of a glue-like substance known as fibrin. Fibrin is nature’s glue and without it Fido would be a big, hairy puddle of strawberry Jell-O. Yay for fibrin!

It’s not always puppies, rainbows and Kevin Bacon’s stabby neck, though. Sometimes blood gets confused and triggers this whole process inside Fido’s body, and a blood clot forms in places that it shouldn’t. A heart attack in a person is basically a blood clot forming inside the blood supply to your heart muscle: when the heart doesn’t get oxygen, it tends to stop.

Sometimes blood can clot in the blood vessels of the lungs, preventing them from picking up oxygen, a phenomenon known as a pulmonary thromboembolism, or PTE.

Cats are especially prone to forming blood clots in their legs. 

Factors like high blood pressure, slow-flowing blood (from sitting too long) and certain genetic diseases can predispose a cat to errant blood clots.

3. Fido’s blood fights cancer and bacteria and viruses and fungus.

His blood also contains white blood cells (WBCs), which basically flow along through the blood looking for trouble. They are like angry little biker gangs, cruising the highways and byways of Fido’s body saying “Tough guy, eh?” to anyone they meet and then roughing them up. If they encounter some bacteria, they have an arsenal of really impressive weaponry with which to kill them.

Most horror-movie villains have one or two tried-and-true methods of dispatching their victims: you’ve got your axe, your chainsaw, your chainsaw grafted onto the stump of your hand, your shotgun, your shotgun grafted onto the stump of your leg. Y’know: the usual.

But WBCs – man, oh man – those guys have all the horror movie weapons beat.

They can shoot toxic chemicals right out of their blobby little bodies and kill and dissolve viruses and bacteria. They can smother bacteria by enveloping them in their blob-like bodies, then finish them off in an acid-bath. They can coat the invaders with proteins that punch holes in them and let all the insides ooze out. And they can release chemical signals that alert other WBC biker gangs that there’s some serious stuff going down and they should come join in the fun. That’s an elevator pitch for the latest Hulu series, right there.

Another thing that WBCs do is fight cancer through xenophobia, which is your basic fear and hatred of strangers or foreigners.

Here’s a scary thought: Right now, somewhere in Fido’s body (and yours), a cancerous cell is swimming around in the blood. Happens all the time. His body has many, many ways to keep that one cancerous cell from falling in love and making more cancerous cells, one of which is his WBCs. They are wonderfully xenophobic and if they see a cell that just doesn’t look right, they go all you ain’t from around here, are ya? on it and take it out of commission. Real world xenophobia = bad; WBC xenophobia = lifesaving.

See? Amazing, right?

Your pet’s blood is a shapeshifting, cancer-fighting biker gang that keeps him alive and healthy every darn day. I feel like that level of awesome deserves some respect.

And maybe a movie deal.