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TED-ED, How the heart actually pumps blood? Edmond Hui

How the heart actually pumps blood? Edmond Hui

Now we know that the heart pumps blood. But that fact wasn't always obvious, because if a heart was exposed or taken out, the body would perish quickly. It's also impossible to see through the blood vessels, and even if that were possible, the blood itself is opaque, making it difficult to see the heart valves working.Even in the 21st century, only a few people in surgery teams have actually seen a working heart. Internet searches for heart function, point to crude models, diagrams or animations that don't really show how it works. It's as if there has been a centuries old conspiracy amongst teachers and students to accept that heart function cannot be demonstrated. Meaning that the next best thing is simply to cut it open and label the parts.

That way students might not fully grasp the way it works, but can superficially understand it, learning such concepts as the heart is a four-chambered organ, or potentially misleading statements like, mammals have a dual-circulation: one with blood going to the lungs and back, and another to the body and back.

In reality, mammals have a figure-eight circulation. Blood goes from one heart pump to the lungs, back to the second heart pump, which sends it to the body, and then back to the first pump. That's an important difference because it marks two completely different morphologies. This confusion makes many students wary of the heart in biology lessons, thinking it signals an intimidating subject full of complicated names and diagrams.

Only those who end up studying medicine compeltely understand how it all actually works. That's when its functions become apparent as medics get to observe the motion of the heart's valves. So, let's imagine you're a medic for a day. What you'll need to get started is a whole fresh heart, like one from a sheep or pig. Immerse this heart in water and you'll see that it doesn't pump when squeezed by hand. That's because water doesn't enter the heart cleanly enough for the pumping mechanism to work. We can solve this problem in an extraordinarly simple way. Simply identify the two atria and cut them off, trimming them down to the tops of the ventricles. This makes the heart look less complicated because the atria have several incoming veins attached. So without them there, the only vessels remaining are the two major heart arteries: the aorta and pulmonary artery, which rise like white columns from between the ventricles. It looks -- and really is -- very simple.

If you run water into the right ventricle from a tap (the left also works, but less spectacularly), you'll see that the ventricular valve tries to close against the incoming stream. And then ventricle inflates with water. Squeeze the ventricle and a stream of water squirts out of the pulmonary artery. The ventricular valves, called the tricuspid in the right ventricle and the mitral in the left, can be seen through the clear water opening and closing like parachutes as the ventricle is rhythmically squeezed.

This flow of water mimics the flow of blood in life. The valves are completely efficient. You'll notice they don't leak at all when the ventricles are squeezed. Over time, they also close against each other with very little wear and tear, which explains how this mechanism continues to work seamlessly for more than 2 billion beats a heart gives in its lifetime.

Now, anyone studying the heart can hold one in their hands, make it pump for real and watch the action unfold. So place your hand above your own and feel its rhymic beat. Understanding how this dependable inner pump works gives new resonance to the feeling you get when you run a race, drink too much caffeine or catch the eye of the one you love.

How the heart actually pumps blood? Edmond Hui Wie pumpt das Herz eigentlich Blut? Edmond Hui ¿Cómo bombea sangre el corazón? Edmond Hui 心臓は実際にどのように血液を送り出しますか?エドモンドホイ 심장은 실제로 어떻게 혈액을 펌프질할까요? 에드먼드 후이 Kaip iš tikrųjų širdis pumpuoja kraują? Edmond Hui Como é que o coração bombeia o sangue? Edmond Hui Как на самом деле сердце перекачивает кровь? Эдмонд Хуэй Kalp aslında kanı nasıl pompalar? Edmond Hui Як серце насправді перекачує кров? Едмон Хюї 心臟實際上是如何泵血的?許偉文

Now we know that the heart pumps blood. これで、心臓が血液を送り出すことがわかりました。 But that fact wasn't always obvious, because if a heart was exposed or taken out, the body would perish quickly. Mas esse facto nem sempre era óbvio, porque se um coração fosse exposto ou retirado, o corpo pereceria rapidamente. Но этот факт не всегда был очевиден, потому что если обнажить или вынуть сердце, тело быстро погибло. It's also impossible to see through the blood vessels, and even if that were possible, the blood itself is opaque, making it difficult to see the heart valves working.Even in the 21st century, only a few people in surgery teams have actually seen a working heart. Также невозможно увидеть сквозь кровеносные сосуды, и даже если бы это было возможно, сама кровь непрозрачна, из-за чего трудно увидеть работу сердечных клапанов. работающее сердце. Internet searches for heart function, point to crude models, diagrams or animations that don't really show how it works. As pesquisas na Internet sobre o funcionamento do coração apontam para modelos grosseiros, diagramas ou animações que não mostram realmente como funciona. Поиски в Интернете по поводу функции сердца указывают на грубые модели, диаграммы или анимации, которые на самом деле не показывают, как это работает. It's as if there has been a centuries old conspiracy amongst teachers and students to accept that heart function cannot be demonstrated. それはまるで、心臓機能が証明できないことを受け入れるために、教師と生徒の間で何世紀も前の陰謀があったかのようです。 É como se houvesse uma conspiração secular entre professores e alunos para aceitar que a função cardíaca não pode ser demonstrada. Как будто между учителями и учениками существует многовековой заговор, согласно которому невозможно продемонстрировать работу сердца. Meaning that the next best thing is simply to cut it open and label the parts. 次善の策は、単にそれを切り開いて部品にラベルを付けることです。 O que significa que o melhor a fazer é simplesmente abri-lo e etiquetar as peças. Это означает, что лучше всего просто разрезать его и пометить части.

That way students might not fully grasp the way it works, but can superficially understand it, learning such concepts as the heart is a four-chambered organ, or potentially misleading statements like, mammals have a dual-circulation: one with blood going to the lungs and back, and another to the body and back. Desta forma, os alunos podem não compreender totalmente o seu funcionamento, mas podem compreendê-lo superficialmente, aprendendo conceitos como o de que o coração é um órgão com quatro câmaras, ou afirmações potencialmente enganadoras como a de que os mamíferos têm uma dupla circulação: uma com o sangue a ir para os pulmões e voltar, e outra para o corpo e voltar. Таким образом, учащиеся могут не полностью понять, как оно работает, но могут понять его поверхностно, изучая такие понятия, как сердце — четырехкамерный орган, или потенциально вводящие в заблуждение утверждения, например, что у млекопитающих двойное кровообращение: одно с кровью, идущей к легкие и спину, а другой в туловище и спину.

In reality, mammals have a figure-eight circulation. 実際には、哺乳類は8の字の循環を持っています。 Na realidade, os mamíferos têm uma circulação em forma de oito. На самом деле, у млекопитающих циркуляция по восьмерке. Blood goes from one heart pump to the lungs, back to the second heart pump, which sends it to the body, and then back to the first pump. O sangue vai de uma bomba cardíaca para os pulmões, volta para a segunda bomba cardíaca, que o envia para o corpo, e depois volta para a primeira bomba. That's an important difference because it marks two completely different morphologies. Trata-se de uma diferença importante porque marca duas morfologias completamente diferentes. Это важное различие, потому что оно отмечает две совершенно разные морфологии. This confusion makes many students wary of the heart in biology lessons, thinking it signals an intimidating subject full of complicated names and diagrams. Esta confusão faz com que muitos alunos desconfiem do coração nas aulas de biologia, pensando que é um assunto intimidante, cheio de nomes e diagramas complicados. Эта путаница заставляет многих студентов с опаской относиться к сердцу на уроках биологии, думая, что оно сигнализирует о пугающем предмете, полном сложных названий и диаграмм.

Only those who end up studying medicine compeltely understand how it all actually works. Só aqueles que acabam por estudar medicina é que compreendem de facto como tudo funciona. That's when its functions become apparent as medics get to observe the motion of the heart's valves. 医師が心臓の弁の動きを観察するようになると、その機能が明らかになります。 É nessa altura que as suas funções se tornam evidentes, uma vez que os médicos podem observar o movimento das válvulas do coração. Именно тогда его функции становятся очевидными, когда медики наблюдают за движением сердечных клапанов. So, let's imagine you're a medic for a day. What you'll need to get started is a whole fresh heart, like one from a sheep or pig. O que precisa para começar é de um coração inteiro fresco, como o de uma ovelha ou de um porco. Для начала вам понадобится целое свежее сердце, как у овцы или свиньи. Immerse this heart in water and you'll see that it doesn't pump when squeezed by hand. Mergulhe este coração em água e verá que não bombeia quando é apertado com a mão. Погрузите это сердце в воду, и вы увидите, что оно не качается при сжатии рукой. That's because water doesn't enter the heart cleanly enough for the pumping mechanism to work. Isto deve-se ao facto de a água não entrar no coração de forma suficientemente limpa para que o mecanismo de bombeamento funcione. Это потому, что вода не поступает в сердце достаточно чисто, чтобы насосный механизм работал. We can solve this problem in an extraordinarly simple way. Podemos resolver este problema de uma forma extraordinariamente simples. Мы можем решить эту проблему необычайно простым способом. Simply identify the two atria and cut them off, trimming them down to the tops of the ventricles. Basta identificar os dois átrios e cortá-los, aparando-os até à parte superior dos ventrículos. Просто определите два предсердия и отрежьте их, обрезав до верхушек желудочков. This makes the heart look less complicated because the atria have several incoming veins attached. Isto faz com que o coração pareça menos complicado porque os átrios têm várias veias de entrada ligadas. Это делает сердце менее сложным, потому что к предсердиям прикреплено несколько впадающих вен. So without them there, the only vessels remaining are the two major heart arteries: the aorta and pulmonary artery, which rise like white columns from between the ventricles. Assim, sem elas, os únicos vasos que restam são as duas grandes artérias do coração: a aorta e a artéria pulmonar, que se erguem como colunas brancas entre os ventrículos. Так что без них там остались только две главные артерии сердца: аорта и легочная артерия, которые поднимаются белыми колоннами между желудочками. It looks -- and really is -- very simple. Это выглядит — и на самом деле — очень просто.

If you run water into the right ventricle from a tap (the left also works, but less spectacularly), you'll see that the ventricular valve tries to close against the incoming stream. Se fizer correr água de uma torneira para o ventrículo direito (o esquerdo também funciona, mas de forma menos espetacular), verá que a válvula ventricular tenta fechar-se contra o fluxo de entrada. Если вы нальете воду из крана в правый желудочек (левый тоже работает, но менее эффектно), вы увидите, что клапан желудочка пытается закрыться против входящего потока. And then ventricle inflates with water. E depois o ventrículo enche-se de água. Squeeze the ventricle and a stream of water squirts out of the pulmonary artery. Aperte o ventrículo e uma corrente de água esguicha para fora da artéria pulmonar. Сожмите желудочек, и из легочной артерии брызнет струя воды. The ventricular valves, called the tricuspid in the right ventricle and the mitral in the left, can be seen through the clear water opening and closing like parachutes as the ventricle is rhythmically squeezed. As válvulas ventriculares, denominadas tricúspide no ventrículo direito e mitral no esquerdo, podem ser vistas através da água límpida, abrindo-se e fechando-se como para-quedas à medida que o ventrículo é ritmicamente apertado. Вентрикулярные клапаны, называемые трехстворчатым в правом желудочке и митральным в левом, можно увидеть через прозрачную воду, открывающуюся и закрывающуюся, как парашюты, по мере того, как желудочек ритмично сжимается.

This flow of water mimics the flow of blood in life. Este fluxo de água imita o fluxo de sangue na vida. The valves are completely efficient. As válvulas são completamente eficientes. Клапаны полностью эффективны. You'll notice they don't leak at all when the ventricles are squeezed. Verifica-se que não há qualquer fuga quando os ventrículos são comprimidos. Вы заметите, что они вообще не протекают, когда желудочки сжимаются. Over time, they also close against each other with very little wear and tear, which explains how this mechanism continues to work seamlessly for more than 2 billion beats a heart gives in its lifetime. 時間の経過とともに、それらはほとんど摩耗することなく互いに接近します。これは、このメカニズムが、心臓がその生涯で与える20億回以上の拍動の間、シームレスに機能し続ける方法を説明しています。 Ao longo do tempo, também se fecham umas contra as outras com muito pouco desgaste, o que explica o facto de este mecanismo continuar a funcionar sem problemas durante mais de 2 mil milhões de batimentos que o coração dá ao longo da sua vida. Со временем они также смыкаются друг с другом с очень небольшим износом, что объясняет, как этот механизм продолжает работать бесперебойно в течение более 2 миллиардов ударов, которые сердце делает за свою жизнь.

Now, anyone studying the heart can hold one in their hands, make it pump for real and watch the action unfold. Agora, qualquer pessoa que estude o coração pode segurar um nas mãos, fazê-lo bombear a sério e ver a ação desenrolar-se. Теперь любой, кто изучает сердце, может держать его в руках, заставить его биться по-настоящему и наблюдать, как разворачивается действие. So place your hand above your own and feel its rhymic beat. Por isso, coloque a sua mão por cima da sua e sinta a sua batida rítmica. Так что поместите свою руку над своей и почувствуйте ее ритмичный ритм. Understanding how this dependable inner pump works gives new resonance to the feeling you get when you run a race, drink too much caffeine or catch the eye of the one you love. Compreender como funciona esta bomba interna fiável dá uma nova ressonância à sensação que temos quando corremos uma corrida, bebemos demasiada cafeína ou chamamos a atenção da pessoa que amamos. Понимание того, как работает этот надежный внутренний насос, дает новый резонанс тому ощущению, которое вы испытываете, когда бежите наперегонки, пьете слишком много кофеина или ловите взгляд того, кого любите.