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12

There are two uses of the term respiration: physiological respiration and cellular respiration Physiological respiration involves the intake of outside oxygen and its distribution to the tissues of the body. Breathing is a part of physiological respiration and functions to bring oxygen into the lungs and expel carbon dioxide. Cellular respiration is a ...


10

Breathing is a part of respiration but respiration is not a part of breathing. Breathing is a process through which oxygen is taken into the body for use in respiration. This involves physical movement to take oxygen (into the lungs) and also chemical action (haemoglobin-carries oxygen from lungs to blood and carbon dioxide from blood to lungs). But ...


8

When we speak, our vocal cords vibrate to the air. Helium makes them vibrate a lot faster (that's what makes the funny sound of your voice after inhaling helium), because its atoms are a lot lighter than nitrogen and oxygen atoms. Obviously, lighter atoms, can travel faster. This faster vibrations are unusual to the cords and they can cause sore throat or ...


8

The veterinarian in our group offers this: For humans, who choke much more frequently than other mammals, it is likely to be a cognitive problem. We talk and eat at the same time and so give ample opportunity to allow food passed the epiglottis and choking. Animals do choke - dogs can, cats can. Not all animals can vomit and this is particularly a problem ...


7

The exact causes of the discomfort relief after the breath-hold breakpoint is unknown yet. It has been stated that breath "pacemaker" continue to work independently of voluntary breath holding. Thus, while breath holding, the breath center is trying to activate the diaphragm and the afferent feedback from the diaphragm normally causes the feeling of ...


6

From the Smithsonian website: Humans are the only mammal that cannot breathe and swallow at the same time, and we are the only species that can choke on its own food. The reason? The lowering of the voice box in our throats (during infancy) enables us to create the enormous range of sounds used in producing language; but this lowering of the voice box comes ...


6

We may be able to voluntarily control our respiratory rate, but only for a short while. The buildup or depletion of CO2 will force us, against our will, to either speed up our respiration or slow it down. So, you can't effectively "fake" your respiratory rate for long, nor, to an astute observer, convincingly. Normal breathing patterns are "normal" for a ...


6

From Boron and Boulpaep textbook of Medical Physiology, second edition, p.289: Because of falling ATP levels in the brain, consciousness is lost within 10 seconds of a blockade in cerebral blood flow. Irreversible nerve cell injury can occur after only 5 minutes of interrupted blood flow. If conscious is lost within 10 seconds of blockade in cerebral ...


5

Via deep scientific analysis (i.e. trying it myself 5 seconds ago), I have determined that you can in fact speak while breathing in, it just sounds funny. Think of the vocal chords as being like the body of a flute. As air passes by them, they vibrate and make sounds. Through careful modulation of their shape, specific sounds can be reproducibly made (this ...


5

To learn obstructive/restrictive lung diseases, I find it easiest to think in extremes at first, with vivid descriptions of why. So in obstructive lung diseases, like COPD/emphysema: Total volume increases because so many of the walls of the alveoli have been destroyed, they are like giant floppy bags instead of nice firm bubbles. There's more empty ...


5

This is more about basic physics than biology. When you hold your breath, you normally take in one last long breath and keep it in as long as possible, Your lungs are therefore already full of gas (remember that the oxygen used by our lungs is only ~22% of the total volume of air you inhale). Therefore, when you release that breath and want to take in a new ...


5

An addition to previous answers plus some clarification The term respiration originally meant breathing i.e inhaling and exhaling (See here). It was believed that it is the oxygen and in turn the act of breathing is what lets an organism survive. After substantial research it had been found that, in individual cells it is the ATP production by ...


4

I'm taking this question at face value. Yes, fish have gills, but we also have a respiratory surface in our lungs so why couldn't we 'breathe' water and extract the oxygen (since extraction is a simple matter of diffusion from the content of the lungs into the blood). Apparently we use 550 L of pure O2 per day. This works out as approximately 400 g. The ...


4

This article quotes a professor of respiratory physiology that says "dogs are built to pant just right. The mechanics of their lungs and chest set a precise rate for panting that minimizes the amount of work while maximizing cooling power." They also don't breathe fully when panting, so they can still cool themselves without increasing gas exchange. This is ...


4

You might need to narrow your parameters a bit. Just things to consider: Our lungs are not hollow organs that can accommodate an oxygen producing machine. They are basically narrow tubes that get smaller and smaller until they end in a tiny balloon-like structure - about 700 million of them. Where would the machine go? 100% oxygen is toxic to the lungs, ...


4

Jerk-like muscle contractions occurring while drifting off to sleep are normal and are referred to as "sleep starts" or sleep myoclonus (National Institute of Health - NINDS). Sleep Education explains the symptoms: Sleep starts usually consist of one strong jerk that affects much of the body. The arms and legs are most likely to be affected. So sleep ...


3

Damage to the brainstem - the part of the brain responsible for controlling breathing and the heart - has different effects on the heart and the lungs. Every heartbeat is not directed by the brain. Instead, the brain has a "throttle" to the heart, by which it can regulate the heart rate up and down, but the actual heartbeat is initiated by special cells in ...


3

I'm not an expert but I think it's pretty obvious.. Bigger animals do require more energy and thus more oxygen for cellular respiration. They also have bigger lungs, although the rythm of the breathing is slower.


3

If we consider another case, there is blood flow, but no new oxygen is coming into the system, the brain cells may begin to die after about four minutes [1]. However, this depends on the person not the amount of time. Consider free divers and more specifically Tom Sietas. These men and women, in this sport, can go well beyond the 5 minute mark with no ...


3

What you are looking for is a spirometer. There are different types of spirometers serving different purposes like the Incentive spirometer and the peak flow meter. I would suggest that you go through the wikipedia page on it to get more info.


3

Just because you have removed the Nitrogen and CO₂ won't help you keep a higher vapour pressure of H₂O in the air. You Could REMOVE all the other gasses and just have O₂ at its normal partial pressure at 1/5 bar total pressure and breath fine, but there would be a fire risk in this environment due to no non O₂ molecules to quench excited O₂. The only way to ...


3

Good question. If you inhale on top of inhaled air this is more work. There is more dead air, air which is not as useful due to the lower concentration gradient. And we breathe more to exhale carbon dioxide than we require oxygen. Low oxygen levels only push us to breathe when oxygen levels are a good deal lower, however tiny changes in carbon dioxide ...


3

I think this is mostly caused by hyperventilation. The excessive breathing disturbs the balance between CO$_{2}$ and oxygen in our lungs. This will cause a http://en.wikipedia.org/wiki/Respiratory_alkalosis (the blood pH, which is normally strictly regulated, gets higher), which can cause dizziness, headaches and fainting. The shift in pH can also disturb ...


3

To my limited knowledge, I believe respiration is the chemical process of the body converting glucose and oxygen into energy, whereas breathing is the physical process of inhaling oxygen and exhaling carbon dioxide. Breathing is somewhat like an "external" respiration.


3

The key point in both cases is that the eggshell and membrane are permeable to oxygen, as you thought. There are subtleties - for instance, the oxygen-permeability of avian (hard-shelled) eggshells changes during development. In the case of eggs laid underground, as in sea turtle eggs, the leathery shell is still permeable to oxygen. The sand restricts ...


3

I found this review which can help to clarify this notion of intra-abdominal pressure : Intensive Care Med. 2009 Jun;35(6):969-76. What is normal intra-abdominal pressure and how is it affected by positioning, body mass and positive end-expiratory pressure? De Keulenaer BL1, De Waele JJ, Powell B, Malbrain ML. The authors mention that there is indeed a ...


2

I don't agree with the accepted answer which seem to assume that food is chewed. I don't think that can be assumed if generally talking about animals and choking. So in addition to Larry's statement of dogs and cats: Fish regularly chokes on prey. Birds can choke. Even dolphins choke:


2

The simplest route to your answer would be through the kcal consumed/expended equation. 1kg (2.2lbs) of fat has ~7700 kcal of energy. The average person requires roughly 2000kcal per day if they perform mild physical labor throughout their day - 25.9% of the total energy available in 1kg of fat. So you could say that if a person did not eat for a day they ...


2

I think you're looking at this the wrong way. Animals evolve to fill niches. Many, many land animals returned to the water as a place to live, including: whales, dolphins, porpoises, seals, sea lions, walruses, manatees, dugongs, otters, hippos, pygmy hippos, crocodiles, sea snakes, sea turtles, river turtles, river snakes, etc. etc. etc. Their ...


2

http://en.wikipedia.org/wiki/Carbon_dioxide#Toxicity "In concentrations up to 1% (10,000 ppm), it will make some people feel drowsy.[83] Concentrations of 7% to 10% may cause suffocation, even in the presence of sufficient oxygen, manifesting as dizziness, headache, visual and hearing dysfunction, and unconsciousness within a few minutes to an hour. ... ...



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