Kw-logo-smaller

The Ins and Outs of the Heart

When most peeps think of the word "heart" they think of love, romance and all that mushy stuff. Those things are great and all, but let's also give your heart props for what it really is - an amazingly powerful life-sustaining organ.

Pump Up the Oxygen

To put it simply, your heart is a pump. Much like that gizmo in your fish tank, your heart moves liquid from one place to another. In the process, the heart re-oxygenates the blood moving through it with the oxygen you breathe in. This is an essential process cuz your blood supplies oxygen to your entire body. If you don't get oxygen for more than a few minutes, you'll die.

Basic Anatomy

Your heart is a cone-shaped muscle in the middle of your chest, right between your lungs. The average adult heart weighs between 9 - 10.5 ounces (255 - 298 grams) and it pumps about 1,900 gallons (7,200 liters) of blood every day. The heart has three layers: the endocardium (outside layer), the myocardium (middle layer) and the pericardium (the fluid sack that surrounds the heart). The heart is also divided up into four chambers, which each have a valve that allows blood to flow in, but prevents blood from flowing backwards.

The Human Heart

In Action

The heart squeezes blood out and into the rest of the circulatory system when it contracts. When it expands, it sucks in poorly oxygenated blood and pushes through the chambers and into the pulmonary artery, where it is re-oxygenated. Then the blood makes its way out of the heart via the aorta and back into the body where it provides your cells with oxygen.

The Human Heart

Did U Know?

  • In the average person's life, their heart will beat 2.5 billion times.
  • Heart disease is the leading cause of death in North America. More than 2,000 Americans die from heart disease everyday.
  • Your heart is about the size of your fist.
Related Stories
16 Comments

latest videos

Poll

What Causes Heart Disease?

  • Genetics.
  • Eating too many high-fat foods.
  • Smoking.
  • All of the above.

related stories

Micro_love_micro
Shay asks: “Love? Is that a real thing, or not? I looked it up in the dictionary, and there was n...
Micro_dating_micro
NSN678 asks: "I asked someone to go out with me and I don't know if we are cause he's giving all ...
Micro_friend_micro
sakotako asks: "I have this HUGE crush on this guy in my class. He’s been my friend for a really ...

Random in the forums

IzzyCloud
IzzyCloud posted in Say Anything:
People hating me.... People bullying me.... People not believing me....... People...annoying the heck out of me........... It's so hard to even think straight anymore!! I had my first anxiety attack, who only knows what the future might hold for me...... I'm so ready to die..... 
reply 24 minutes
AlphaT
AlphaT posted in Debating:
"hollybl2468" wrote: "-Karpov-" wrote: That doesn't have anything to do with what I said   It has everything to do with what you said. Every generation thinks they're better than the previous one. History repeats itself because human beings are arrogant and believe we're superior to everything, whether it's older generations or in this case, animals.  ...That's because we are. We have no reason to change our position in the animal kingdom. We are the superior species. 
reply about 1 hour
Rustybird
Rustybird posted in Say Anything:
Anxiety isn't something that can be described as a feeling or emotion. It is instead almost like a rain cloud. I use this rain cloud analogy because it doesn't fit the base of a shadow nor demon. Have you ever seen one of those rain clouds on cartoons that follow people around where ever they go? Anxiety is similar to that however unlike a shadow you will always know it's there and whenever you approach a social situation the rain gets heavier, and as you become weaker from surviving the heavy rain sometimes you take the easy way out and avoid the social situation altogether. You eventually feel helpless to the rain and give in, you avoid any social situation possible and begin to lose all skill in that area. Little did you know doing this to avoid heavy rain will instead set you up for a storm. A storm of awkwardness and low self esteem and that's when the dark thoughts seep in.  However there will be those people who will protect you for the storm, or those people who would be there if you needed them to and if you put in just a little effort you can evade the storm and though that little rain cloud may always linger around you, you will never forget about your experience in the storm, from that you grow as a person and eventually you will accept and laugh about this little rain cloud. You will accept yourself for who you are and push yourself beyond your boundaries to become the person you wanted to be. This person may not be perfect but if you are happy with the person you are then none of that should matter. None of the awkwardness, none of the mistakes and none of the imperfections should matter.  The only thing that does matter is the fact that you are the person you want to be. The person you are happy being. (Just my experience with anxiety /: ) I had a lot to get off of my chest)
reply about 1 hour
Desmondlove1
Desmondlove1 posted in Debating:
We all know that the symbols and colors of God are only white. And devils color is red and black which stand for danger. I came to ask why did Satan choose two colors and mixed it together to make it scared and danger? And my another question is why did we always obey devils work and ignored Gods work? On my own mind i can say that is girls is the most human that do devils work, 95% and they do God work 5% But we guys can only do 40% of devils work and 50% for God.      Please if its false or true  story you can drop your comment below ........................................................... ...................................................................... ....................................................................................   What i understand in all these is   that  Satan is greedy and he came to destroy the world for those who give them chance like Nigeria have already give them chance, so is there for you  to choose one of this two masters God or Satan, because i know you cannot serve two masters at the same time;     Please give your vote with choice. .......................................................... ...................................................... .................................................. ............................................................... ...................................................................                             Thanks for your cooperation and thanks for your understanding                                                                       Sign by Desmond        
reply about 1 hour
hollybl2468
hollybl2468 posted in Debating:
"-Karpov-" wrote:That doesn't have anything to do with what I said It has everything to do with what you said. Every generation thinks they're better than the previous one. History repeats itself because human beings are arrogant and believe we're superior to everything, whether it's older generations or in this case, animals. 
reply about 2 hours

play online games