full transcript

From the Ted Talk by Edmond Hui: How the heart actually pumps blood

Unscramble the Blue Letters

For most of history, humans had no idea what purpose the haert served. In fact, the organ so confused Leonardo da Vinci, that he gave up studying it. Although everyone could feel their own heart beating, it wasn't always clear what each tuhmp was achieving. 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 vsseles, and even if that were possible, the blood itself is opaque, making it difficult to see the heart vlaves 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 terhceas and setdntus to accept that heart function cannot be dstenemratod. mieanng 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 raielty, mammals have a figure-eight colatiiucrn. Blood goes from one heart pump to the lungs, back to the second heart pump, which sndes it to the body, and then back to the first pump. That's an important difference because it mraks two completely different morphologies. This confusion makes many students wary of the heart in biology lessons, thinking it sagnils an intimidating subject full of complicated nmaes and diagrams. Only those who end up studying mecdniie compeltely understand how it all actually works. That's when its fiunnotcs become apparent as medics get to observe the motion of the heart's valves. So, let's imagine you're a midec 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 etenr the heart cnalely enough for the pnipmug mechanism to work. We can solve this problem in an extraordinarly spmlie 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 vines attached. So without them there, the only vessels rniaimeng are the two major heart arteries: the atroa 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 surceatacllpy), you'll see that the ventricular vavle tries to csloe against the incoming stream. And then ventricle inflates with water. Squeeze the ventricle and a stream of water striuqs out of the pulmonary atrrey. The ventricular valves, called the tricuspid in the right vrnicltee and the mitral in the left, can be seen through the clear water onpeing and closing like parachutes as the ventricle is rmtyahlihcly 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 pclae 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.

Open Cloze

For most of history, humans had no idea what purpose the _____ served. In fact, the organ so confused Leonardo da Vinci, that he gave up studying it. Although everyone could feel their own heart beating, it wasn't always clear what each _____ was achieving. 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 _______, and even if that were possible, the blood itself is opaque, making it difficult to see the heart ______ 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 ________ and ________ to accept that heart function cannot be ____________. _______ 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 _______, mammals have a figure-eight ___________. Blood goes from one heart pump to the lungs, back to the second heart pump, which _____ it to the body, and then back to the first pump. That's an important difference because it _____ two completely different morphologies. This confusion makes many students wary of the heart in biology lessons, thinking it _______ an intimidating subject full of complicated _____ and diagrams. Only those who end up studying ________ compeltely understand how it all actually works. That's when its _________ become apparent as medics get to observe the motion of the heart's valves. So, let's imagine you're a _____ 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 _____ the heart _______ enough for the _______ mechanism to work. We can solve this problem in an extraordinarly ______ 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 _____ attached. So without them there, the only vessels _________ are the two major heart arteries: the _____ 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 _____________), you'll see that the ventricular _____ tries to _____ against the incoming stream. And then ventricle inflates with water. Squeeze the ventricle and a stream of water _______ out of the pulmonary ______. The ventricular valves, called the tricuspid in the right _________ and the mitral in the left, can be seen through the clear water _______ and closing like parachutes as the ventricle is ____________ 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 _____ 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.

Solution

  1. functions
  2. squirts
  3. students
  4. valve
  5. rhythmically
  6. ventricle
  7. aorta
  8. signals
  9. teachers
  10. circulation
  11. cleanly
  12. vessels
  13. sends
  14. demonstrated
  15. opening
  16. artery
  17. names
  18. medic
  19. veins
  20. spectacularly
  21. meaning
  22. place
  23. remaining
  24. marks
  25. heart
  26. medicine
  27. simple
  28. thump
  29. valves
  30. pumping
  31. enter
  32. close
  33. reality

Original Text

For most of history, humans had no idea what purpose the heart served. In fact, the organ so confused Leonardo da Vinci, that he gave up studying it. Although everyone could feel their own heart beating, it wasn't always clear what each thump was achieving. 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.

Frequently Occurring Word Combinations

Important Words

  1. accept
  2. achieving
  3. action
  4. animations
  5. aorta
  6. apparent
  7. artery
  8. atria
  9. attached
  10. beat
  11. beating
  12. beats
  13. billion
  14. biology
  15. blood
  16. body
  17. caffeine
  18. called
  19. catch
  20. centuries
  21. century
  22. circulation
  23. cleanly
  24. clear
  25. close
  26. closing
  27. columns
  28. compeltely
  29. completely
  30. complicated
  31. concepts
  32. confused
  33. confusion
  34. conspiracy
  35. continues
  36. crude
  37. cut
  38. da
  39. day
  40. demonstrated
  41. dependable
  42. diagrams
  43. difference
  44. difficult
  45. drink
  46. efficient
  47. enter
  48. explains
  49. exposed
  50. extraordinarly
  51. eye
  52. fact
  53. feel
  54. feeling
  55. flow
  56. fresh
  57. full
  58. fully
  59. function
  60. functions
  61. gave
  62. grasp
  63. hand
  64. hands
  65. heart
  66. history
  67. hold
  68. humans
  69. idea
  70. identify
  71. imagine
  72. immerse
  73. important
  74. impossible
  75. incoming
  76. inflates
  77. internet
  78. intimidating
  79. label
  80. leak
  81. learning
  82. left
  83. leonardo
  84. lessons
  85. life
  86. lifetime
  87. love
  88. lungs
  89. major
  90. making
  91. mammals
  92. marks
  93. meaning
  94. mechanism
  95. medic
  96. medicine
  97. medics
  98. mimics
  99. misleading
  100. mitral
  101. models
  102. morphologies
  103. motion
  104. names
  105. notice
  106. observe
  107. obvious
  108. opaque
  109. open
  110. opening
  111. organ
  112. parachutes
  113. parts
  114. people
  115. perish
  116. pig
  117. place
  118. point
  119. potentially
  120. problem
  121. pulmonary
  122. pump
  123. pumping
  124. pumps
  125. purpose
  126. quickly
  127. race
  128. real
  129. reality
  130. remaining
  131. resonance
  132. rhymic
  133. rhythmically
  134. rise
  135. run
  136. seamlessly
  137. searches
  138. sends
  139. served
  140. sheep
  141. show
  142. signals
  143. simple
  144. simply
  145. solve
  146. spectacularly
  147. squeeze
  148. squeezed
  149. squirts
  150. started
  151. statements
  152. stream
  153. students
  154. studying
  155. subject
  156. superficially
  157. surgery
  158. tap
  159. teachers
  160. teams
  161. tear
  162. thinking
  163. thump
  164. time
  165. tops
  166. tricuspid
  167. trimming
  168. understand
  169. understanding
  170. unfold
  171. valve
  172. valves
  173. veins
  174. ventricle
  175. ventricles
  176. ventricular
  177. vessels
  178. vinci
  179. wary
  180. watch
  181. water
  182. wear
  183. white
  184. work
  185. working
  186. works