Lub-dub | Sound Of Heart
That’s the “dub” you hear—the end of the heartbeat’s working cycle. After the dub , there’s a brief pause. That’s your heart relaxing, refilling with blood, and getting ready for the next lub-dub . The silence is as important as the sound—it’s rest time for your hardest-working muscle. What If the Rhythm Changes? Healthy hearts don’t always sound like a metronome. Your heartbeat naturally speeds up when you breathe in and slows down when you breathe out—that’s called sinus arrhythmia , and it’s totally normal (especially in young people).
Let’s break down the simple genius behind the . The Short Answer: Two Sounds, Two Actions Your heart is a double pump. The lub happens when the upper chambers (atria) squeeze blood into the lower chambers (ventricles) and the valves between them snap shut. The dub follows when the lower chambers pump blood out to your body and lungs, and the exit valves snap shut. lub-dub sound of heart
Think of it like a heavy door swinging shut. Now the blood is rocketing out of the ventricles—one to the lungs (via the pulmonary valve), the other to the body (via the aortic valve). When the ventricles finish contracting, these two exit valves snap closed. Because these valves are under higher pressure, the sound is sharper, shorter, and higher-pitched: dub . That’s the “dub” you hear—the end of the
That’s the “dub” you hear—the end of the heartbeat’s working cycle. After the dub , there’s a brief pause. That’s your heart relaxing, refilling with blood, and getting ready for the next lub-dub . The silence is as important as the sound—it’s rest time for your hardest-working muscle. What If the Rhythm Changes? Healthy hearts don’t always sound like a metronome. Your heartbeat naturally speeds up when you breathe in and slows down when you breathe out—that’s called sinus arrhythmia , and it’s totally normal (especially in young people).
Let’s break down the simple genius behind the . The Short Answer: Two Sounds, Two Actions Your heart is a double pump. The lub happens when the upper chambers (atria) squeeze blood into the lower chambers (ventricles) and the valves between them snap shut. The dub follows when the lower chambers pump blood out to your body and lungs, and the exit valves snap shut.
Think of it like a heavy door swinging shut. Now the blood is rocketing out of the ventricles—one to the lungs (via the pulmonary valve), the other to the body (via the aortic valve). When the ventricles finish contracting, these two exit valves snap closed. Because these valves are under higher pressure, the sound is sharper, shorter, and higher-pitched: dub .
Sci-Hub is the most controversial project in today science.
The goal of Sci-Hub is to provide free and unrestricted access to all scientific
knowledge ever published in journal or book form.
Today the circulation of knowledge in science is restricted by high prices. Many students and
researchers cannot afford academic journals and books that are locked behind paywalls.
Sci-Hub emerged in 2011 to tackle this problem. Since then, the website has revolutionized the
way science is being done.
Sci-Hub is helping millions of students and researchers, medical professionals, journalists and
curious people in all countries to unlock access to knowledge.
The mission of Sci-Hub is to fight every obstacle that prevents open access to knowledge: be it
legal, technical or otherwise.
To get more information visit the about Sci-Hub section.
