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19

Unlike erythrocytes that have a very rigid shape and almost cannot change their size (hence the size distribution is indicative and can be used for diagnostic purposes in medicine), lymphocytes can change their size in a wider range, this is why you see the numbers 6-9 and 10-15 μm. And they indeed cluster into several different groups: so-called "large ...


19

Red blood cells are initially produced in the bone marrow with a nucleus. They then undergo a process known as enucleation in which their nucleus is removed. Enucleation occurs roughly when the cell has reached maturity. According to one research (Ji, et al., 2008), the way this occurs in mice is that a ring of actin filaments surrounds the cell, and then ...


15

I've been doing a little more digging myself and have found a couple of other advantages: Risk of Venous-thromboembolism (deep vein thrombosis/pulmonary embolism (1)). Blood group O individuals are at lower risk of the above conditions due to reduced levels of von Willebrand factor(2) and factor VIII clotting factors. Cholera Infection Susceptibility ...


14

The less antigens a woman (or in fact a female of any species close enough to humans for this phenomenon) has, the higher are the risks of triggering an immune reaction during her pregnancy, if the child has those antigens. The Rhesus incompatibility is probably the most common case of this problem. One could thus assume that in populations that are ...


13

summary: O2 could form a linear complex with the Fe atom, but then it would start to look more like a mineral Fe=O...O bond - a linear bond would be like a transition state to an iron oxide (rust). An Fe-O-O bent bond preserves more of the electronic character of the O2 molecule and promotes strong but reversible binding to Hemoglobin. The oxygen ...


13

According to the Wikipedia entry for the ABO blood group system: Anti-A antibodies are hypothesized to originate from immune response towards influenza virus, whose epitopes are similar enough to the α-D-N-galactosamine on the A glycoprotein to be able to elicit a cross-reaction. Anti-B antibodies are hypothesized to originate from antibodies produced ...


13

The red colour of blood isn't actually to do with food at all. The primary purpose of the blood is to carry oxygen to all the cells that require it to release energy. Red Blood Cells are filled with an iron containing pigment called haemoglobin. When it has oxygen bonded to it, haemoglobin has a bright red colour - it is this that gives blood its red ...


10

Most likely they were measuring the hemoglobin concentration, in units of g/dL (i.e. 101 kg/m3). Assuming by your username you are male, the reference range for [Hb] is approximately 13.8 to 18.0 g/dL (sources vary somewhat), which roughly matches the "19" you were told was the upper bound. Wikipedia also notes that [Hb] "is typically tested before or after ...


9

The blood of the fetus does not mix with the blood of the mother. Instead, the placenta provides a system where the two separate blood streams flow past each other with thin separation allowing nutrients to flow between the two streams but the not the blood cells and other large components.


8

I want to know can +ve and -ve blood group of a couple could be a cause of miscarriage in pregnancy? Yes. In extreme cases, it can. You are talking about Rh Incompatibility, and can become a big issue when the mother has Rh(-) blood and the father has Rh(+) blood (such as the case with your cousin and his wife). What could have happened (but definitely ...


8

Your question has many questions in it. As for the evolution of Rh factor, Blancher and Apoil (2000) attribute the high level of sequence similarity (92%) of the two RH locus genes, RHD and RHCE to a gene duplication event in the common ancestor of human, chimps, and gorillas. Their analysis of the cDNA from these genes revealed "complex recombination ...


7

First of all we should distinguish between the physiological clotting factors that are parts of the normal clotting pathways, and those that might affect clotting pathways but are not observed under healthy conditions. TPA (tissue plasminogen activation), PAI-1 (plasminogen activator inhibitor) and prothrombin are normal clotting factors that are essential ...


6

This could be a very long answer, but I'll try to keep it brief. The first thing to understand is what causes the anaemia. I'm going to refer to defective haemoglobin found in a sickle cell patient as HbS and normal haemoglobin as HbA. Under certain circumstances (low O2 concentrations) the HbS protein is prone to aggregating into long filaments. Here is ...


6

Substances such as blood trigger the Cough reflex, so if for any reason blood accumulates in the airways, it will be ejected this way. If you have a look at chest anatomy, you can see how this could be caused (look at Trachea down to the lungs, aorta and the carotid arteries above the heart). A shot through the chest can peforate many large blood vessels, ...


6

Mammalian tongues are red because of haemoglobin. Blue/black colouration is due to the additional presence of melanin. At the boundary between the epidermis and dermis are melanophores, cells that contain melanin. This brown pigment absorbs ultraviolet radiation from the sun that might otherwise damage the underlying dermal tissue. Melanin in the dark ...


6

We each inherit either A, B, AB or no antigens from our parents. The current thought is that when you're between 0-6 months old you are exposed to bacteria/viruses that contain very similar antigens (A or B). These antigens are similar enough to the A and B antigens found on red blood cells that any antibody created against these bacterial antigens would ...


5

The oxygen saturation (in lungs) and desaturation (in target organs) takes place via diffusion along the concentration gradient (i.e. partial pressure for gases). Therefore as long as RBCs from two different sources and having different partial pressure of oxygen mix up, the oxygen level starts to equilibrate between these cells. But diffusion as a passive ...


5

The oxygen-carrying capacity of the blood is: amount of haemoglobin * % saturation The average blood donation is approximately 10% of total blood volume. . Since the donation will have no effect on the % saturation, the oxygen-carrying capacity at each altitude will go down by 10%. By inspection of the graph in the question, the % saturation goes down ...


5

Antibodies and other immune responses do indeed occur against the donor's white blood cells. However, white blood cells are present in relatively tiny quantities (3-10 million WBCs per ml of blood vs 4-6 billion cells per ml). Because the number of WBCs is so low, the immune reaction to them is also proportionally lower, with fever being a typical (and ...


5

Not really no. Most blood transfusions we think about are red blood cells or platelets, which don't have the immune function you're asking for. That's a good thing. Usually, if there are white blood cells in the transfused blood, the host's immune system will recognize them as foreign and destroy them. Remember, your cells all look like foreign invaders ...


4

The key feature of type O blood as "universal donor" is that the incoming red blood cells have neither A nor B antigens and so the resident antibodies (anti-A , anti-B) will not react with them. Since transfusions are carried out with packed red blood cells the plasma antibodies of the donor don't matter - they will not be introduced into the recipient.


4

The molecular basis of copper-transport diseases in Trends in Molecular Medicine, Volume 7, Issue 2, 1 February 2001, Pages 64–69, has a link to a 1973 paper by JM Gillespie entitled "Keratin Structure and Changes with Copper Deficiency," stating Menkes patients are often diagnosed from their unusual hair structure – termed pili torti – also known as ...


3

It's pretty straightforward. White blood cells have all the usual organelles while mature red blood cells are missing most of them. WBC can have specialized lysosomes depending on their function, as well as granules if they are granulocytes. This goes into the different WBC types in some detail.


3

In short: The extrinsic cascade reacts to damages of the blood vessel, the intrinsic pathway reacts to damages of the walls. But as with all things, the long version is ways more complicated: The extrinsic pathway is activated when you damage tissue and factor VII come in contact with tissue factor (also known as factor III). Tissue factor is located in the ...


3

If by a fasting state, you mean blood glucose levels, researchers seem to think it is feasible. See for example Pleitez et al. (1) and Guo et al. (2). Their designs both utilize infrared IR laser light to measure glucose levels in the skin.


2

To add a more concise answer: Yes, the conflict between positive and negative Rh (Rhesus) blood groups can cause miscarriage. The genetic makeup decides whether red blood cells (RBC) carry a specific surface protein known as Rhesus factor (Rh). If your own RBCs do not carry this protein (Rh-), your body will consider it (or RBC carrying it) a foreign ...


2

The T315l mutation of BCR/ABL gene produce the complete resistance of CML leukemia to all currently available BCR/ABL inhibitors. There is a idea that is not yet tested for such patients - allogenic hematopoietic transplatation. More information: http://www.ncbi.nlm.nih.gov/pubmed/20657522 ...


2

just to add on to the previous reply... Shown to be in mice & rats (and sick humans), the cell-cell interaction between a macrophage (this is a big engulfing cell required for immunity) and young red blood cells (RBC), is known as the erythroblastic island (commonly known as EBI). If u googled it, there is a scientific review in 2008 that describes this ...


2

I can answer only half your question. It is not necessary that the child has to have the blood group of parents. The inheritance is like this : 1.There are 3 alleles Ia , Ib and Io. 2.Ia and Ib are codominant i.e. they will both be expressed if present together. 3.Ia and Ib are dominant over Io. So, blood group O can only be expressed if the genotype is ...



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