Heart 101 | National Geographic

Heart 101 | National Geographic

– [Narrator] The heart pumps
blood throughout the body. Carrying oxygen and
nutrients to every cell. It’s this circulation
of blood that is vital to sustaining life. The heart is an organ made up of several tough layers of muscle. The pericardium is the thin
layer that covers the exterior while the endocardium
lines the inside walls. The heart is divided into four chambers. Two upper and two lower. The upper chambers known
as the atrium receive blood coming into the heart. The lower chambers are the
ventricles that pump blood out. Between each chamber are
valves that open and close and help keep the blood moving. They are the tricuspid, mitral, pulmonary, and aortic valves. A pumping cycle starts
when oxygen repleted blood returns to the heart after
circulating throughout the body. The blood enters through the
right atrium before flowing to the right ventricle. It’s then pumped to the lungs
via the pulmonary arteries. There blood is rejuvenated
by air that’s breathed in. The oxygen rich blood
returns to the heart through the left atrium where it
goes to the left ventricle. Then by way of the aorta artery
the fresh blood is pumped throughout the body before
the process repeats itself. That process happens with every heartbeat. And it’s relentless. The heart beats 100,000 times a day. 40 million times a year and up to three billion times
over an average lifespan. But there are conditions
that can disrupt a heartbeat and that normality. They can range from myocardial
infarction or heart attack to heart disease and hypertension. In contrast, exercise
and emotional excitement can also have an impact
on a person’s heartbeat. The various blood vessels that comprise the circulatory system are a
network of veins, arteries, and capillaries that
span over 60,000 miles throughout the body. And the heart is the
pump at the center of it. (heartbeat)

100 Replies to “Heart 101 | National Geographic”

  1. I've always been fascinated by the ❤️ heart especially the pericardium after surgery it's a water sac 🤷‍♂️💧 during my life study of medicine An after witnessing 1'st hand at least 4 open heart surgeries. I'd learned incredible things however usually my shift would end an I
    Still had questions but, it's ok we still all are learning we are fearfully and, wonderfully made . Thankyou for sharing
    Godspeed Sincerely from LarryWhittington 😁👍❤️

  2. I remember learning about the heart in anatomy class & we had to study all the terms right
    And I was talking to my lab partner about the vocab & what I do to study fast so I was like "Yeah I just keep reading the terms aloud until I have it down by heart you know?" and I continued on without realizing I made a pun 💀
    My teacher laughed & my lab partner pointed out my pun to me & that's when I was like oop 💀💀

  3. I love this channel and its educational topics. I love your channel and please post more about this it is so interesting on how the body worked

  4. The heart is the most important organ that allows humans to live. The heart allows the blood in our bodies to circulate through the body. So when a heart problem occurs, humans become very dangerous. Let's eat a lot of heart-healthy foods.

  5. no wonder why people said to someone they love..

    “.. you're my heart.."

    its mean that You're so Important to me


  6. What makes the Heart "beat" ??
    I mean what makes it to CONTRACT, Relax and again CONTRACT..
    It's like pressing the Heart with your Hands..

  7. Looks like i should stop reading subjective books and start learning things because learning is better than just copy pasting what you remember

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