104
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How can a person be kept alive while being periodically drained of blood?
Open a blood bank and pay people for blood. People can give half a litre per donation and then go home.
It's much cheaper than trying to keep them alive using machines.
Build it in the poor areas ...
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94
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Other blood colors
There are many proteins that transport oxygen in the terrestrial biosphere, this, and this.
One thing to note is that at human body temperature, atmospheric pressure, and Earth's atmospheric ...
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78
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How many nanobots can I have in my blood?
For simplicity, let's pretend these are well designed nanobots that don't outright kill their host by blood clots or accidentally ripping holes in capillaries. So let's pretend these great scientists ...
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77
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What colour would our blood be if our blood was based on gold?
Frame challenge: Gold isn't reactive enough to react with oxygen (or most any common gas really) so that blood can carry be a transport for it. The reason our blood is iron-based is because iron is ...
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66
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Why would vampires require human blood?
Immunology:
The need for human blood is not, really, about food. It's about antibodies.
The vampire's immune systems have come to function in a completely different way from human immune systems. This ...
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60
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Why would a blood transfusion of midiclorians not make my force abilities stronger?
Because the blood level midichlorian equilibrium point is determined by your body's biochemistry. You can't alter this by adding more midichlorians. All that does is cause a temporary imbalance (way ...
60
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Can blood form snowflakes?
It's hard to believe but I have some RL experience with freezing blood (cow blood!). It freezes rather well, but at lower temperatures (about -5C). When it freezes blood "essence" (this red-...
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How long after death is blood fit for consumption?
For a starting point, consider the meat aisle at the grocery store. In it you'll find roasts, steaks, and other chunks of red meat. This government food-safety site says that such meat can be kept ...
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53
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Where could a vampire get blood without harming people?
However, it turns out most of the “blood” in rare meat is myoglobin, and that the blood is drained from the animal at the slaughterhouse before it is butchered and sold.
and
Blood from ...
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53
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Where could a vampire get blood without harming people?
Since you say it doesn't have to be human blood, they would just straight up buy frozen animal blood by the bucket at supermarkets like nobodies business. No need for any fancy subterfuge or ...
52
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Could a humanesque creature derive all its nutrients from drinking blood?
The simple answer is yes it's possible, if they have a suitably developed physiology. Vampire bats, leeches, mosquitoes and more are proof of that. There are complications that make it less practical ...
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48
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What would happen if a refrigerated bag of human blood was warmed up in a normal kitchen microwave?
Ask a Blood Banker:
If we are to assume that the vampire wants the blood to be in something like the native functional state (otherwise the vampire could simply live off of meat), then this is a ...
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46
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How reflective is blood?
Consider two substances with refractive indices $n_1$ and $n_2$. The reflectivity can be calculated as
$$R=\left|\frac{n_1-n_2}{n_1+n_2}\right|^2$$
For air, $n\approx1$, and for water, $n\approx1.33$. ...
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46
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What could a Medieval society do with excess animal blood?
Eat it: Turn it into black pudding. Or drink it, perhaps mixed with milk.
BTW, the druidic religion sacrificed animals, as well as probably humans. In the absence of Christians and Romans it's not ...
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45
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How can a person be kept alive while being periodically drained of blood?
No Near Death Draining Required - this is Business.
Ask the Blood Donation Clinic near you.
Thirteen humans at a time (the max amount) are placed inside this machine and hooked up to it through a ...
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45
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Why would a blood transfusion of midiclorians not make my force abilities stronger?
Midichlorians are not what gives you the force, they are a by-product of being strong in the force. Excess psychic energy goes into making the midichlrians. All that blood is wasted because the ...
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39
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What colour would our blood be if our blood was based on gold?
Gold III Oxide is describe as being "brown or brownish-black powder at room temperature" though the pictures I can find look red or orange. If you had a gold based hemaglobin (auru-globin), ...
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38
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What could a Medieval society do with excess animal blood?
Growing the sacred crops.
Blood is an excellent fertilizer.
You talk about the blood not being able to touch the ground, but then you ask for domestic or commercial uses for it. So either enough ...
37
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Would a vampire still be able to be a practicing Muslim?
Allah is Forgiving and Merciful.
In the case of eating forbidden food, the Qur'an offers an out for those who really did not want to eat it, but were compelled to by hunger. The Islam stack exchange ...
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How can a 15-year-old vampire get human blood?
She has transfusion dependent anemia.
source
Her blood is low. Doctors can't figure it out! She does not seem to have an inherited disease like sickle cell. Her marrow is not normal but she does ...
- 273k
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How reflective is blood?
I spent some time considering how you might even start forming an ocean of blood.
Mammal blood is out of question because it would coagulate. It would probably end up with rocks made of blood crust ...
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31
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How well could a dog pick out the scent of a single person in a pool of carnage?
I saw a documentary where they were training a young, rescued bloodhound as a tracker. One of the tests was where the subject (to be tracked) went to a baseball game (in a stadium). So their scent was ...
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30
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How can a 15-year-old vampire get human blood?
Bitcoin, Tor, a PO box, and express shipping with dry ice.
Totally possible to buy on the black market.
News source 1
News source 2
News source 3
News source 4
My governments "What can I import&...
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29
votes
Why would vampires require human blood?
T Cells
A less fantastic version of DWKraus’s excellent answer. Your vampires have evolved a symbiotic relationship with humankind. Vampires can produce their own antibody-crafting B-cells, and can ...
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28
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How much blood does a vampire need?
This the nutritional information of lamb's blood. I will use it as an approximation for real blood. They would lack vitamin A (bad sight... live in the dark... that makes sense), potassium, and they ...
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28
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How can a person be kept alive while being periodically drained of blood?
Actually, what you want to do here is not drain the blood out of a person, but replace it with something else until the person's natural systems start to reproduce what has been lost.
In other words, ...
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27
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Can blood form snowflakes?
Probably not. Snowflakes - at least the pretty multi-branched ones - take a rather long time to grow, perhaps 25 minutes or so, as they drift down from the upper atmosphere: https://www.noaa.gov/...
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26
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Robots with (specifically red) blood
You could have hydraulics. Hydraulic arms are routinely used in heavy machinery. In the first Terminator movie the Terminator was finally defeated by a hydraulic press. Hydraulic robots are real....
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25
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What can I do to make blood black?
Blood is More Than Red Blood Cells
If you look at the things required for a complete blood count, you're going to notice that there are things which are not red blood cells but are still "blood".
...
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25
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How long after death is blood fit for consumption?
It is Not (for some mythologies)
It should be noted that the blood of the dead is poison to vampires in a number of mythologies and stories.
For example in interview with a vampire.
! Claudia ...
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