Questions tagged [blood-circulation]

Tag for questions regarding the circulation of blood through out the organism and issues that may arise from dysfunction of systemic circulation.

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Why does our face get red during anger?

My attempt: This site says that it is due to flight or fight mechanism, which results in more amount of blood being passed to face causing red face. But isn't it wasteful for our body to send more ...
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2answers
70 views

Isolating the vasculature of an organ?

Is there a chemical or process that would dissolve or remove all other tissues in an organ and leave all the vasculature intact? I am planning to make a shelf display of the blood vessels in the heart ...
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0answers
146 views

How superficial an artery has to be for pulse to be measured manually? [closed]

Why arteries pulse? How superficial an artery has to be for pulse to be measured manually?
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1answer
114 views

What is the difference between ferritin and hemoglobin?

I have been reading that ferritin is the store of iron but hemoglobin is actually the amount of this in blood. Does hemoglobin get sourced from ferritin? Is it possible for a person to be low on ...
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2answers
145 views

Are there any exceptional cases in which a person with O negative blood group cannot donate?

Are there any exceptional cases in which a person with O negative blood group cannot donate or any case in which compatibility might not be established between O negative an any other blood group?
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1answer
88 views

A hypothetical emergency situation

This question was posed to me by my Biology teacher: Consider a hypothetical emergency situation of a person shot by a bullet in the heart. The bullet goes into the body and comes out from it, ...
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1answer
452 views

What is the speed of blood in when flows through the fingertip?

What is the average speed of blood as it flows through the index finger on the right hand?
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23k views

Exsanguination Time from Damage to Major Arteries

For a game project, I need to study how much blood loss is suffered when the major arteries of the human body are severed. I believe there are medical textbooks that have collected data on blood ...
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1answer
789 views

Are tergo-sternal muscles of cockroach involved in blood circulation?

Tergosternal muscles help in the blood circulation in a cockroach as well as in movement of the wings for flying. I came across a question that claims that these muscles are used in blood circulation ...
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1answer
2k views

Common site for atherosclerosis

My book( textbook of anatomy abdomen and lower limb 2nd edition - by vishram Singh pg.no:286) says: Acute arterial occlusion: It is mostly caused by embolism or thrombosis. It usually occurs in the ...
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2answers
915 views

If someone's arm is cut off, how does that affect blood circulation throughout their body?

Essentially what I'm asking is that if someone's arm is amputated, doesn't that cut off a significant part of their blood flow because the blood vessels that normally flowed up to the hand of the ...
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1answer
379 views

Vo2 of the brain is 21% of Q=13% or of the entire blood?

I am reading now the book which states that the Q (blood flow per unit of time) of the brain is 13% while the Vo2 (relative Oxygen used per unit of time) is 21%. Now my question is if the Vo2 of the ...
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0answers
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What is the surface area of the cardiovascular system?

In this question says: An adult human has been estimated to have some 60,000 miles (96,560 km) of capillaries with a total surface area of some 800–1000 m2 (an area greater than three tennis ...
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1answer
110 views

Cell nanoparticle dynamics within blood

I am trying to mathematically model the dynamics of a particular cell in circulation and its binding to another nanoparticle that is intravenously injected. The concentration of this cell is very low (...
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0answers
27 views

How do bats manage lymph fluids?

We all know that bats hang upside down to sleep. I was watching some sleep for a while, and they don't move much while asleep. If I fall asleep sitting in a chair my lower legs will swell. Lymph ...
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0answers
82 views

Does capillary blood pressure have any effect on how much oxygen or nutrient gets distributed to tissues?

From what I have read regarding blood pressure and blood flow, I've come to the conclusion that, apart from the osmolarity of blood, the only determinant of how much oxygen/nutrients the tissues get ...
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1answer
468 views

Is Infra Red light safe to use on your scalp? [closed]

I own an Anodyne Infrared therapy device which I use to treat ligament/tendon/muscular pains and it works nicely. I see other infrared products used to combat hair loss (e.g. https://www.amazon.com/...
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0answers
29 views

Is the CNS vascularized?

I was under the impression that the CNS is never penetrated by blood vessels, which explains why one never sees them in histological samples. However a google search reveals I am wrong. So can ...
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130 views

Is there a naturally occurring mechanism in the body for cleaning plaque buildup in arteries?

Is there a naturally occurring mechanism in the body for cleaning plaque buildup in arteries ?
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78 views

What is the circulation that allows for nutrient absorption and excrete of metabolic wastes in humans? [closed]

Pulmonary veins carry oxygenated blood from lungs to heart, while pulmonary arteries carry deoxygenated/CO2 rich blood from heart to lungs. On the other hand, systemic arteries carry oxygen-rich blood ...
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1answer
326 views

distribution of some injected materials/medicines through blood vessels [closed]

Fastest distribution of some injected materials/medicines & with no risk of any kind can be achieved by injecting it into - artery or vein?
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1answer
530 views

What is the relationship between stroke volume of blood and ventricular end-diastolic volume? [closed]

I do know what each term means. That is, i know that stroke volume is: the volume of blood pumped by each contraction of a ventricle, while ventricular end-diastolic volume is: the volume of blood in ...
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1answer
668 views

Why doesn't the rest of the body have something like the “blood-brain” barrier to protect itself from pathogens?

According to Wikipedia: "The blood–brain barrier acts very effectively to protect the brain from most pathogens". This is because the pathogens cannot pass through the tight junctions of the ...
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1answer
9k views

Do camels have nucleated RBCs or enucleated RBCs?

Most mammals have enucleated RBCs as an adaptation to facilitate the transport of oxygen. My text says that camels and llamas are exceptions to these. I was wondering why they are exceptions, and the ...
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1answer
333 views

What would happen if blood flow wasn't periodic?

Blood pressure has its systolic and diastolic parts due to the beating heart and the body's used to that kind of thing. What would happen to a person supported by a blood-pumping machine that applies ...
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1answer
285 views

Why is it always Sodium that we talk of in blood pressure?

Why is that we emphasize so much on sodium in blood pressure? I understand that it is a major extracellular ion, but, it also is tightly regulated. So when something is that tightly regulated, won't ...
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0answers
263 views

Is the amount of blood same in the pulmonary and systemic foetal circulation?

We learn that the stroke volume is the same for the right and left side of the heart. So the amount of blood in either circulations should also be the same. (is it? I myself doubt this statement. As ...
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1answer
840 views

What is the oxygen carrying capacity of reticulocytes?

What is the oxygen carrying capacity of immature red blood cells, or reticulocytes? Is there any difference between oxygen carrying capacity of mature and immature red blood cells?
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1answer
201 views

When there's a wound, the end result is a thrombus or thrombosis?

When there's a wound, the blood vessels are damaged. To stop the loss of blood, the clotting cascade starts off and forms a clot. This clot is a thrombus, right? Seems like perfect physiology. Where ...
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50 views

Oncotic (Osmotic Pressure) in the blood pressure

I just wanted to ask, why is the oncotic pressure more negative in the blood plasma even though the hydrostatic pressure is higher since the blood comes from the pumping of the heart?
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0answers
303 views

How long does it take for blood to travel from the lungs to the fingertips?

I've noticed that a pulse oximeter at my fingertip lags my breathing effort by a noticable amount. I conclude that it takes some time for freshly oxygenated blood to travel from the lungs to the ...
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1answer
9k views

What is the speed of blood?

The speed of blood may vary from one place to another and may be quite low in the tiniest vessels compared to the biggest one. What is the speed of blood while exiting a normal human heart?
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2answers
634 views

Diffusion coefficient of cells in blood?

What's the diffusion coefficient of white cells in blood? Is it well defined, or are cells too large and few as to be treated as particles in this context? P.S. I have tried to look this up, but what ...
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1answer
2k views

How do cellular waste products enter arterial blood?

I recently learned that blood in renal arteries contains waste materials, which is filtered via nephrons in the kidneys. My question is, how are these waste materials getting into the arterial blood?...
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1answer
1k views

Why is alcohol purged from the body more slowly when we sleep?

It is a popular belief that when you get asleep after drinking alcohol, in the morning you have higher level in your blood than if you stayed awake the whole night. Is this true? If so, why? Is it ...
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1answer
7k views

what makes our body warm?

I would think that there would so many chemical reactions going inside our body,friction produced by blood in veins, subcutaneous and visceral fat acting as heat insulators. I was wondering to what ...
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2answers
138 views

By What Mechanism Does Heat Cause Muscle Relaxation?

Heat is commonly used "loosen" muscles, but what exactly is happening to relax the muscle? It wouldn't make sense that increased blood flow alone would relax muscle.
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844 views

Why is squeezing not recommended after a needle prick?

I've read some interesting things about the risk of infection after a needle prick (30% - hepatitis B, 1.8% - hepatitis C and 0.3% - HIV), but I've also saw that the local squeezing is not recommended....
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2answers
3k views

Why do veins undergo vasoconstriction during physical activity?

How would this help increase blood circulation?
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0answers
138 views

How do mosquitoes react to blood feeding on a highly ethanol intoxicated host?

Considering that a mosquito can consume up to five times its body weight in blood during a single meal (Encyclopedia of the Arctic, M.Nuttal), and considering a very strong alcoholic intoxication of ...
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0answers
76 views

Can bigger persons generally resist g-forces better?

I've seen a claim that bigger persons generally resist g-forces worse than smaller in an undergraduate biology book. However this claim was supported by the argument that blood has to travel a longer ...
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1answer
2k views

Is pulse rate measurable in the capillary bed and venous vasculature?

Pulse rate is easily felt when gently pressing the arteries in the wrist or neck region (Fig. 1). Fig. 1. Feeling the pulse at the radial artery. Source: Wikipedia Arteries supply the thin ...
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3answers
25k views

Why does the face turn pale in dangerous situations?

I know what the effects are of a dangerous situation on the brain, i.e., an activation of the hypothalamic-pituitary-adrenal (HPA) axis which eventually results in an increased heart rate and elevated ...
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3answers
14k views

Are blood vessels organs?

Are blood vessels classified as organs? Organs compose of 2 or more tissues and perform a certain function. Blood vessels have 3 different tissues and perform a function (transport blood), yet I do ...
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1answer
925 views

Oxygenated hemoglobin in MRI

I have read the following sentence: Because this oxygenated hemoglobin is unaffected by magnetic fields, the response RF signal returned to the fMRI scanner is stronger when there is more brain ...
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1answer
770 views

Are there fishes with a double circulatory system?

Our courseware materials say there are such fishes, but my Internet searches suggests fishes only have a single circulatory system.
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1answer
120 views

Where does the exudate comes from during inflammation?

During inflammation transudate and exudate is formed by vessels. I would like to make sure if it comes from arterioles, venules, or both, and the reason why.
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1answer
430 views

Difference between pulse and blood pressure

I'm a very naive and biologically illiterate person, and from what I've read on the internet I'm not really sure I understand the difference between pulse and ...
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1answer
45k views

Why do fingers swell during cold winters?

When exercising, tissue in the hands may swell. This may be caused by the muscles generating heat, which leads to blood being pushed to the vessels closest to the surface of your body to dissipate the ...
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1answer
4k views

How does the brain cool itself?

Thoughout life everyone tells you that brain is essentially a computer but just like computers your brain would create immense amounts of heat by being in use, so if that's the case how does it cool ...