The study of blood, the blood-forming organs, along with blood diseases and their treatment.

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22
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4answers
9k views

Is there any advantage to one blood type over another?

All humans can be grouped into ABO and Rh+/- blood groups (at a minimum). Is there any advantage at all to one group or the other? This article hints that there are some pathogens that display a ...
19
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1answer
527 views

Are lymphocyte sizes clustered in two groups?

Tortora writes in Principles of Anatomy and Physiology: Lymphocytes may be as small as 6–9 μm in diameter or as large as 10–14 μm in diameter. Those ranges are quite close to each others. Should ...
18
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3answers
15k views

Why do mammalian red blood cells lack a nucleus?

How did the red blood cell in humans get to lose its nucleus (and other organelles)? Does the bone marrow just not put the nucleus in, or is it stripped out at some stage in the construction of the ...
13
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2answers
5k views

Why do people have antibodies against other blood types?

The ABO blood type divides each blood type according to whether they have the "A" and "B" antigen(s) (AB has both, O has none). People also have antibodies against the antigens they don't have (AB has ...
13
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5answers
6k views

Origin, or source, of rhesus negative in human blood

This is my first post here, so please be gentle. I recently learned that I have Rh- blood (I'm A-), and was idly looking into blood types on Wikipedia. I was surprised to find that relatively few ...
11
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1answer
1k views

Why does oxygen bind to hemoglobin in an specific angle?

There is an specific angle of the bond between oxygen and hemoglobin in lungs, which I don't know, but what interests me more is the question, why is it specific?
9
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1answer
85 views

Why do so many people have group O blood?

Please forgive me in case my question wouldn't make much sense. I was reading about ABO blood groups on Wikipedia, where I learnt that O is a recessive allele, and that it seems the A allele predates ...
9
votes
1answer
188 views

What are the clotting factors' effect on avascular necrosis development?

Do clotting factors tpa and pai-1 lead to degenerative osteoarthritis in the same way that lupus anticoagulant and prothrombin might? Is one of these pathways particularly detrimental during formation ...
8
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1answer
189 views

Does the oxygen concentration equilibrate between red blood cells in the liver sinusoids?

In the sinusoids of the liver, venous blood from the hepatic portal system mixes with arterial blood from the hepatic arteries. Do oxygen molecules move between oxygenated RBCs and non-oxygenated ...
7
votes
1answer
236 views

When giving blood, what is the specific Iron measurement they take?

I went to give blood the other day, and they take an "iron" measurement prior to actually drawing the blood. My level was 16.4 -- but what specific type of iron were they measuring? I've heard of ...
6
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2answers
7k views

Can positive and negative blood type of a couple lead to miscarriage?

I want to know can $+ve$ and $-ve$ blood group of a couple could be a cause of miscarriage in pregnancy?
6
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1answer
52 views

Why ml scale blood retrieval is required to run a blood test?

Substances found in blood are present at microscopic scale and tend to be invisible to the unaided eye. Why is a whole vial of blood (at ml scale) is required to assess the presence and concentration ...
6
votes
1answer
181 views

Does a blood transfusion cure disease?

Does transferring blood between two people also transfer all the white blood cells? Why can't AIDS victims with low t-cell count just get blood transfusions till they have more t-cells? Why can't ...
6
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1answer
38 views

Why extract DNA from certain white blood cells instead of whole blood?

In my lab, human DNA is extracted from whole-blood samples. I don't actually do the extractions and I am not familiar with the specific protocol but I understand that platelets and red blood cells ...
5
votes
1answer
206 views

Are tongues red because they contain blood?

Many animals have red tongues, though not all of them - blue-tongued skinks and giraffes come to mind. Are they red because of the blood (and therefore haemoglobin) in them? It sounds plausible, but ...
4
votes
1answer
153 views

How can the child and the mother have different blood types?

As far as I know the fetus is fed by the umbilical cord which basically connects his/her circulatory system with the mother's in order to supply oxygen and nutrients. But how is this possible if they ...
4
votes
1answer
58 views

Why don't individuals with sickle cell trait suffer from sickle cell anemia?

Ostensibly, in people with sickle cell trait, half of the hemoglobin in their body would be defective. Is it actually the case that sickle cell hemoglobin is produced in equal amounts? If not, how ...
4
votes
1answer
63 views

Blood consumption

Is consumption of blood more "dangerous" compared to meat? There was a news-article about unnatural chemicals found in the blood of mothers. This reminded me about a question I have pondered upon ...
4
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1answer
95 views

Why isn't RH disease present in other mammals?

Basically, I have read about RH disease, Its rare but it can happen when an RH + baby is conceived by an RH - mother. This raises many questions. I have heard this problem only happens with humans, ...
4
votes
1answer
97 views

Is it possible to condition the body to reduce bruising?

I do combat sports, and in these sports there are a lot of hits that can cause bruising. I've found that, over time, physical conditioning can reduce and/or eliminate the bruising to the point where ...
4
votes
1answer
80 views

What percentage of human capillaries are located in the skin?

As in the subject line, what percentage of capillaries in a human (expressed in terms of total length, I suppose) are located in the skin, as opposed to internal organs? Google scholar has not turned ...
3
votes
1answer
638 views

Why does blood come from mouth when people are shot in the chest area?

In almost every movie scene when a character is shot in the chest area, some blood comes from his mouth or sometimes even coughs blood before he dies. Are these kind of scenes realistic/possible? If ...
3
votes
1answer
1k views

How much does donating blood affect the amount of oxygen in your blood stream at high altitude?

I am a regular blood donor and I am also a skydiver. We normally go to around 13,000 feet AGL (above ground level). Depending on how high above sea level the ground is, altitudes could be as high as ...
3
votes
1answer
36 views

why does blood when oxidized over time become bluish green?

Oxygenated blood is bright red and deoxygenated blood is dark red or brown. If you take oxygenated blood and leave it in the air it will turn dark red, then brown, then finally a bluish green from ...
3
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1answer
22 views

External tissues, connected to the body?

Some cancer tumors suppress themselves from spreading. When such tumors are removed by surgery, the metastasis process is accelerated. Isn't it possible to put such tumors into external device like ...
3
votes
2answers
1k views

What is the genetic basis of blood type (ABO) system?

What is the genetic basis of the A/B/B+/O/etc. blood type system? Are there definitive loci that correspond to each or can multiple different genotypes produce the same antigen profile? Also, is the ...
3
votes
1answer
71 views

When was the purpose of bone marrow discovered?

I'm currently reading William Cheselden's book Osteographia or The Anatomy of the Bones, which was published in 1733 (for the pretty pictures, naturally; not up to date anatomy). When he addresses the ...
2
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2answers
377 views

Do females living on mountains have more RBCs than a normal male [closed]

I got this doubt when I was studying about haematocrit value. According to my NCERT textbook males have greater number of RBCs than females. But who will have more RBCs when comparing a normal male ...
2
votes
1answer
67 views

Why are red blood cells considered to be cells?

Wikipedia states that a cell is the basic structural, functional and biological unit of all known living organisms. Cells are the smallest unit of life that can replicate independently. It then ...
2
votes
1answer
117 views

Does Blood Loss Shorten Telomeres?

If blood loss necessitates immediate cell division to replace lost cells, does the increase in cell division correlate to shortening of telomeres? Does it further cause the Hayflick Limit to be ...
2
votes
1answer
141 views

Can antibodies be formed against white blood cells after blood transfusion?

If antibodies are produced against other blood groups' red blood cells, why can't antibodies form against white blood cells, of any blood group? (even the same one, as MHC will be different in almost ...
2
votes
1answer
257 views

Why does hemoglobin's affinity for oxygen increase if an organism lives at a higher elevation where oxygen is lower?

Wouldn't its affinity for oxygen decrease because the acidity of the body would increase with the lack of oxygen? The textbook said otherwise though and I don't understand.
2
votes
1answer
1k views

Presence of MHC on red blood cells

Do red blood cells have no MHC? (I have often heard that they do not.) If so why are they not destroyed by immune cells?
2
votes
1answer
816 views

What happens if an IV drip with a saline solution slips out of the vein, but keeps dripping into the body?

A patient has a saline solution IV drip into the vein. They have somehow moved around and the needle has fallen out of the vein, but remained in the body. Nobody has noticed and for a few hours water ...
2
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1answer
67 views

Why it is so difficult to treat leukemia?

I want to ask what is the reason that T315I type CML leukemia is currently untreatable. I have read quite a few papers in this subject. Why the current genetic oriented engineering drugs failed to ...
2
votes
2answers
411 views

What is the best color for a PPG signal (photoplethysmography)?

What is the best color for a PPG signal? Red, green, blue or infra-red? I'm asking because commercial oximeter sensors usually use a pair of red and infra-red LEDs. But recently, I've seen a lot of ...
2
votes
0answers
25 views

Does apheresis damage any components of blood? If not, why not?

Blood donation involving apheresis is becoming increasingly common. It looks like the process involves centrifuging blood at very high speeds* before removing the desired fraction and returning the ...
1
vote
2answers
101 views

What actually are the blood groups for human being?

We all know that, Human blood groups are of 4 types with Negative and Positive of each types. The Wikipedia article also states so. But according to this forum thread there are some other types too: ...
1
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2answers
610 views

Antigen Antibody reactions during blood donation

A person wih blood group O is called a Universal Donor. Well, his plasma contains antibodies A and B. During blood donation, if blood group O is given to a person with blood group A (since blood group ...
1
vote
2answers
404 views

Iron deficiency anemia symptoms explanation

In my classes and on the internet, brittle nails and dry hair (or hair loss) are described as symptoms of iron deficiency anemia, but none explains the cause of such symptoms. Does anyone have any ...
1
vote
1answer
54 views

Can gelatine digestion make blood more thick?

Can gelatine cause blood thickening if digested?
1
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1answer
44 views

Carbon Monoxide and High-Oxygen-Affinity Varieties of Hemoglobin

I recently learned about the concept of "affinity" in regards to hemoglobin. For hemoglobin in humans, carbon dioxide has a lower affinity than oxygen, which allows gas exchange to occur in our lungs. ...
1
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1answer
49 views

Trauma, blood loss and thirst

Back story. Watched an episode of Arctic Air, (season three episode six), where they are practicing and hoping to become a licensed search and rescue airline. Anyhow; two hikers gets attacked by a ...
1
vote
1answer
23 views

Detecting a Fasting State in the Body via Lasers

I was just wondering wether it would be possible to detect if the body is in a "fasting" state, via lasers attached to the body. If it is possible, what sort of laser would be needed?
1
vote
1answer
92 views

Why do you need the intrinsic pathway when you have faster extrinsic pathway?

There are two pathways in blood clot fromation; the extrinsic pathway and the intrinsic pathway. The extrinsic pathway is faster than intrinsic pathway because it has less number of steps. So, why do ...
1
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1answer
63 views

Prothrombin time when extrinsic pathway is turned off

I was searching for an answer that "why do we need intrinsic pathway when there is fast extrinsic pathway" and i found the answer in the following link: http://www.pathologystudent.com/?p=3197 It ...
1
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1answer
52 views

Blood group probability question

My answer ( after rounding off) is 9% -100( 0.75 X 0.25 X 0.5) but the answer given is 22 % Am I correct ?
1
vote
1answer
402 views

Why is prothrombin time test not used for heparin

Prothrombin time test is used for the monitoring of warfarin but not heparin. Why is this used for warfarin monitoring and why is it not used for heparin monitoring?
1
vote
1answer
151 views

How do proteins get into the blood stream?

So I'm asking this in reference to the injection of insulin, which is commonly done subcutaneously (in the hypodermis, a fatty part of skin). Now I know proteins usually get into the blood when ...
1
vote
1answer
38 views

What Effect would Cannabinoids have on the Acute Porphyrias?

I should be clear in saying that this question is NOT intended for personal medical advice. Rather what I am looking for is journal articles and/or books that touch on this subject because I think it ...