99 votes

Can a person survive on blood in place of water?

Blood is not a good source of water. 1 liter of blood contains about 800 mL of water, 170 grams of protein and 2 grams of sodium (calculated from the composition of lamb blood). When metabolized, 170 ...
Jan's user avatar
  • 8,079
52 votes
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Does animal blood, esp. human, really have similar salinity as ocean water, and does that prove anything about evolution?

Short answer Early sea water had a very different osmolality than blood plasma. Background The reference range of serum osmolality is 275–295 mosm/kg (mmol/kg) (MedScape). The osmolarity of sea water ...
AliceD's user avatar
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35 votes
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Can a cancerous cell from outside cause cancer in a healthy person?

Can a cancer cells from someone else's body cause cancer in a healthy person? No. Cancer cells from another person cannot cause cancer in a healthy person. The rare cases of transmissible tumors all ...
De Novo's user avatar
  • 8,791
29 votes

Does animal blood, esp. human, really have similar salinity as ocean water, and does that prove anything about evolution?

The argument that blood plasma resembles sea-water, in essence, relies on the notable similarity in concentration of two ions in plasma and sea-water, compared with their intracellular concentration: ...
user338907's user avatar
  • 4,723
27 votes

Can a cancerous cell from outside cause cancer in a healthy person?

Before OP edited his/her question, it was a little unclear whether the question was only about humans. The following answer is more general than asked as it also considers cancers in non-humans Most ...
Remi.b's user avatar
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18 votes

Can a person survive on blood in place of water?

You can drink blood of course to a minimalistic amount (eg- a few teaspoons ) and also if blood is free from pathogens. But it should always be in very small amounts and from suitable donor. Here's ...
Ishi's user avatar
  • 559
17 votes
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Which type of test tube should not be used for blood collection?

Your reasoning is sound and correct. The answer key is wrong. An unclotted blood sample needs something to prevent clotting. Extracellular calcium is required for both the coagulation cascade and ...
De Novo's user avatar
  • 8,791
15 votes
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How does aspirin "thin" blood?

Aspirine irreversibly inhibits the enzyme cyclooxygenase. This enzyme facilitates the reaction from arachidonic acid to prostaglandin G2/H2. The further reaction leads to the generation of Thromboxane ...
Chris's user avatar
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14 votes

Why does the affinity of haemoglobin for oxygen decrease at high altitudes?

The answer to this question is yes, a decrease in oxygen affinity will decrease the oxygen taken up by the haemoglobin (Hb), but it is an appropriate response because it will have a greater effect in ...
David's user avatar
  • 25.7k
13 votes

Why isn’t Haemoglobin a plasma protein, rather than being encompassed by the erythrocyte?

To the man with a hammer, everything looks like a nail. The poster’s hammer seems to be kidney function. Mine is the biochemistry of the erythrocyte (red blood cell). Others, no doubt will be able to ...
David's user avatar
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12 votes
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Why does the affinity of haemoglobin for oxygen decrease at high altitudes?

Haemoglobin's job is to transport oxygen and not store it. Therefore it should also be able to release oxygen effectively. When the differences in partial pressure of oxygen between the tissues and ...
WYSIWYG's user avatar
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12 votes
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Can you bleed from your bones?

Yes, bones too bleed if they get damaged (break or bruise). This is because bones are highly vascularised organs and breaking of bones will indeed rupture the blood vessels causing bleeding. Main ...
JM97's user avatar
  • 4,796
12 votes
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What's the smallest animal with hemoglobin running in its veins?

It depends how different from human hemoglobin it can be and still count as hemoglobin. Here is a cool evolutionary tree of globins. http://www.mhhe.com/biosci/genbio/enger/student/olc/art_quizzes/...
Willk's user avatar
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10 votes

Why isn’t Haemoglobin a plasma protein, rather than being encompassed by the erythrocyte?

An additional aspect is that the availability of iron usually constrains the growth of pathogens. Cassat and Skaar in "Iron in Infection and Immunity" state: Iron is an essential nutrient for both ...
mgkrebbs's user avatar
  • 9,054
10 votes

Can a person survive on blood in place of water?

Here is a specific account of a person surviving at sea drinking turtle blood, while eating some fish and drinking some rain water. Several peoples have a habit of drinking raw animal blood, at least ...
Peter - Reinstate Monica's user avatar
8 votes
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Blood clumping in mosquitos

Female mosquitoes need blood for laying their eggs. This actually means that they need a source of rich protein and iron for their kids and hence, prey on us. It is worthwhile for us to pause here ...
Polisetty's user avatar
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8 votes
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Why do red blood cells maintain Iron in the Haem group in the +2 (ferrous) oxidation state?

Q. “What problems (if any) arise when the iron is oxidised?” A. Haemoglobin will be converted to methaemoglobin which cannot bind oxygen. To quote from the article on Methaemoglobin in Wikipedia:...
David's user avatar
  • 25.7k
7 votes

What do bloodsucking animals actually feed on?

Lets find out how much calories are there in the blood. I am using this site for main reference, but will also add more references where needed. But before that, we should know that one donation of ...
another 'Homo sapien''s user avatar
7 votes
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What is "multiple" myeloma?

J. Von Rustizky, a Russian pathologist working in the laboratory of Friedrich von Recklinghausen (1833–1910) in Strassburg in 1873, introduced the term “multiple myeloma.” At autopsy, a 47-year-old ...
Alan Boyd's user avatar
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6 votes
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Why do people perceive blood pressure as the force that moves the blood forwards (see details)?

In the vascular system, pressure is what moves blood forwards, at least in an analogous manner to voltage...just like voltage, pressure itself doesn't move things, but a pressure gradient does. You ...
Bryan Krause's user avatar
  • 45.7k
6 votes

Is there a purpose for nucleated red blood cells in reptile, avian and fish blood?

It's difficult for vertebrates to aquire/evolve enucleated cells, that's why they are very rare previous to the mammalian adaptation. Salamanders have evolved enucleated cells. Research suggests that ...
bandybabboon's user avatar
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6 votes
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Is there a specific suffix for "within a cell"? i.e. in a similar manner to how -aemia refers to within the blood

"Cyto"/"cytic" and similar are common prefixes/suffixes to refer to things associated with cells; however they don't necessarily specify intracellular space, they are more often referring to specific ...
Bryan Krause's user avatar
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6 votes
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How are monocytes larger than capillaries?

They aren't completely rigid and can change shape to squeeze through (see Downey et al). If they are activated, monocytes can get stuck in capillaries and block them, which contributes to poor ...
Bryan Krause's user avatar
  • 45.7k
6 votes

Why does the luminal test need hydrogen peroxide?

wouldn't there already be oxygen present within the blood itself or from the environment that would react with the luminol itself? I'd say that's the exact reason why peroxide is added. Without ...
X Zhang's user avatar
  • 354
5 votes
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How is the probability of Rh type inheritance calculated?

There are four possible parental genotype combinations (R = Rh+ allele, r = Rh- allele): m f RR RR Rr RR RR Rr Rr Rr Only the last can produce Rh- offspring. ...
adjan's user avatar
  • 2,106
5 votes
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Why does high EDTA concentration cause swelling of platelets?

As it's reported in an old 1968-article by J. G. White: Chelation of membrane calcium by EDTA appears to cause marked irregularities in the platelet wall and massive swelling of the canalicular ...
DavideN's user avatar
  • 180
5 votes

Why does high EDTA concentration cause swelling of platelets?

I think your question is relying on two completely different definitions of "high" EDTA. Really, both concentrations are "high" but one of them is "really really high." The only references (for ...
Bryan Krause's user avatar
  • 45.7k
5 votes
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Why does applying pressure to a venipuncture site prevent haematoma?

Prevention of hematoma (as we say in the colonies) is by causing hemostasis within the vessel (here, a vein). Careful pressure during withdrawal, followed by firm pressure after withdrawal until ...
De Novo's user avatar
  • 8,791
5 votes
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What would the RBCs of someone heterozygous for sickle cell anemia look like?

The peripheral smear in a patient with sickle cell trait typically appears normal (see Cecil Medicine Ch. 166). Each cell has only 30-40% HbS, and so the polymer that causes the sickling doesn't ...
De Novo's user avatar
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