96

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 grams of protein yields the amount of urea that requires 1,360 mL of water to be excreted in urine (calculated from here); 2 grams of sodium requires about ...


53

Veins have several advantages over arteries. From a purely practical standpoint, veins are easier to access due to their superficial location compared to the arteries which are located deeper under the skin. They have thinner walls (much less smooth muscle surrounding them) than arteries, and have less innervation, so piercing them with a needle requires ...


36

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 involve unhealthy or not yet developed persons. Transmission of tumor cells from one individual to another happens, but is quite rare, and in all cases ...


31

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 ...


31

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 &...


28

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 cancers are not transmissible but some are. We call them (clonally) transmissible cancers. Transmissible cancers The most famous case of transmissible cancer ...


21

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 ...


21

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 ...


20

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

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 ...


19

Hemoglobin molecules used to manufacture these products are not contained by a red cell membrane, and when released into the vasculature, these molecules rapidly scavenge nitric oxide.This can result in systemic vasoconstriction, decreased blood flow, increased release of proinflammatory mediators and potent vasoconstrictors, and a loss of platelet ...


19

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 why The strange fact is, blood, when drank, is toxic. When confined to places where blood is supposed to be — such as the heart, vessels, and so on — it is ...


18

Blood is considered a type of connective tissue (sometimes). However, an organ is formed of multiple different tissues. Thus, blood is a tissue, not an organ.


16

This is an embryonic stem cell on the tip of a needle photographed on a scanning electron microscope (SEM). The image was taken by Steve Gschmeissner, see here for the original.


16

It is a direct correlation between the ABO blood groups and the Roman numerals. O: I A: II B: III AB: IV This numeric system was pioneered by Jan Jansky of Czechoslovakia in the early 20th century. Apparently it is still used in some former Soviet states. Erb IH. 1940. Blood Group Classification (A Plea for Uniformity). Can Med Assoc J 42(5):418-...


16

Right of the bat, veins are superficial so it is much easier to hit a vein than an artery. Arterial sticks are very difficult if you are not practiced at them while veins are much much easier. Also arterial sticks have a very specific purpose usually for example arterial blood gas. Also veins are low pressure compared to the higher pressure of arteries so ...


15

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

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 ...


12

The "purest of all blood" is fresh out of the bone marrow, i.e. in your circulatory system. Menstrual blood is a combination of blood, some mucous, and dead endometrial tissue. The endometrium consists of a single layer of columnar epithelium resting on the stroma, a layer of connective tissue that varies in thickness according to hormonal influences. ...


12

Nothing. Rhesus incompatibility results when people who are Rh- develop antibodies against Rh+ blood after exposure. People with Rh+ blood do not show any such reaction to Rh- blood. In a way, it's comparable to blood types in that regard. People with the blood group O can develop antibodies against type (for example) B blood. People with type B don't ...


12

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 artery which supplies blood to bone is nutrient artery , others are epiphyseal, metaphyseal and periosteal arteries. Skeletal system receives about 15.6% of cardiac ...


12

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/genbiomedia/0329.jpg Here is the worlds smallest fish. Fish have hemoglobin similar to that of humans. from Wikipedia: The world's smallest fish is ...


12

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 provide yet different perspectives. From a biochemical point of view the erythrocyte has a limited repertoire of metabolic pathways compared with other ...


11

Typically transfusions are indicated for hemoglobin < 7 g/dL (for adults normally: 12-15 grams per deciliter [1]) or < 8-10 g/dL if there is cardiac disease where diminished oxygen carrying capacity cannot be compensated by increased cardiac output. The answer above is theoretical because there is no accurate way to measure blood loss in the clinical ...


11

Just my 2-cents worth as visual add-on to @MattDMo 's answer: Blood smear showing red blood cells and two white blood cells at 400x. Source: Microscope Master Human red blood cells 1000x. Source: Wikipedia Human white blood cells 2000x. The small dots (red arrow) are Diplococcus gonorrhea bacteria (Neisseria gonorrhoeae), each ~0.5 micrometers in diameter....


10

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 ...


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 ...


10

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, ...


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