Circulatory system and the heart | Human anatomy and physiology | Health & Medicine | Khan Academy

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Introduction to the circulatory system and the heart. Created by Sal Khan.
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Health & Medicine on Khan Academy: No organ quite symbolizes love like the heart. One reason may be that your heart helps you live, by moving ~5 liters (1.3 gallons) of blood through almost 100,000 kilometers (62,000 miles) of blood vessels every single minute! It has to do this all day, everyday, without ever taking a vacation! Now that is true love. Learn about how the heart works, how blood flows through the heart, where the blood goes after it leaves the heart, and what your heart is doing when it makes the sound “Lub Dub.”
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[@IAmTheNietzsche]

"He has eyeballs, and he's looking at us!" haha I love these videos, helpful without being boring, beats the hell out of my biology textbook

[@DeeandA8]

This lecturer is totally inspiring... I was completely engaged and motivated. He took a complex organ such as the heart and it's circulatory system and made it quite simple to comprehend in minutes... Unfortunately, my professors did not possess this skill.

[@Mificsai]

12 years later and I'm in college pursuing a nursing degree. Anatomy and physiology class is more difficult for me than I anticipated so THANK YOU!!! It was also VERY nostalgic to hear your voice and see your writing again! Put me in a better headspace

[@goodyeoman4534]

Same. I loved watching these videos when I was doing my Physiology degree. I'm having a bit of a refresher now and by some miracle I can actually remember most of it. Good luck with your nursing degree.

[@ThaFooooosa]

Guys this guy is amazing! Making biology understandable with a slight touch of humour - He has never timed how long it takes for a blood cell (i think it was) to go all around the body. SO much better then being stuck in the lab having no idea whats going on

[@goodyeoman4534]

It takes about one minute for the entire 5 litres of blood to pass through the heart.

[@jakew8612]

All you people with khan academy are awesome. I dont know who is talking through this video but i have been watching your videos for years and you are so extremely good at getting the important points across with no confusion. Sincere thanks.

[@IsmaVLCM]

You told and teached me everything i needed to know for this system. I love your videos and your demonstrations. THANKS. Keep your good work!!!!!

[@stylegal20]

wow!seriously you are the perfect teacher for me.i like your diagrams and your handwriting and you have great detail for colour which i love!the colours you use are very nice and you explain very clearly and funny.i should have seen this earler instead of wasting my whole afternoon trying to see the heart.thanks:)

[@ADDAN143]

This man is the kind of humanbn that makes this world livable. Thank u khan for your time and help.

[@MatthewGiuffrida]

Thanks man great video, really helpful and I understand everything for my end of the year exam tomorrow!!! Thank you so much!!!

[@pilaroka]

This is sooo cool. I am in my first year of nursing and You are a life saver!

[@goukimess]

This guy is GOOD. Even I understood the circulatory process of the heart in a way that my professor isn't able to. I'm gogn to check this guy out for more videos. Now I have more hope in my A& P II class.

[@imegatrone]

Nice Video Introduction to the circulatory system and the heart That You Share , So Very Nice Thanks You

[@Krust108]

So much better than my biology teacher!

[@SoSeo4321]

before i watched your videos, i was crying about the fact that i had no clue what was going on with the whole heart and all, now im sooooo happy!!! i know it!!!

[@emgabrielle]

im almost in love with every single vid you've put up! theyre all fantastic

[@meltean14]

Very good video. Khan is a very good teacher!

[@yifangwei]

Thank you, Professor Khan! I am always looking forward to new videos!

[@adriudrik]

Caution! This guy explain things so greately that you could easily been kept engaged during the whole video, as it happened to meeeee... =XP, despite the fact I don't like biology.... up to right now! Thanks master, you're awsome transmitting contents easily and enjoyably.

[@johnturk158]

Two months struggling with the heart. Understood it in 10mins. Wow.

[@chetansonthalia5368]

yeah this video made it like its standard 1's maths

[@babatundeadefila6734]

You explain sooo well Keep up the good work

[@CIWIAyo]

SO HELPFUL. You literally taught me and clarified a weeks worth of anatomy in about 15 minutes. Thank you so much

[@Daski69]

I never feel the same kind of joy in any other activity than teaching. When you struggle with the understanding of a new concept, be it math, physics, chemistry or biology and when you eventually grasp it and it all becomes crystal clear, is an exhilirating experience Then you go on explaining what you've just learned to an attentive friend while actually understanding what you're teaching and not quoting what you remember the teacher saying before the break. SALMAN KHAN FOR PRESIDENT

[@norwayte]

Great. It really works... painting/writing and explaining in real time. Otherwise it would be a screen-captured, commented Power-Point-Movie... means a pseudo sophisticated way to explain nothing and distract people from the content with the pseudo-ability to program things and send them into coma - no matter the subject. Your way to "present" should be spread around the world - from schools to offices to... Keep on going.

[@atlastfq]

Thank you very much, The lyric is very helpful for foreign med-students like me.

[@drifty8889]

Thanks ;)

[@AlhajiAjalloh-j1p]

Good biology teacher,thank you

[@ivan92ivanov]

@Jokuim yes i've wondered the same thing, and according to wikipedia, my books and so on, I'm pretty sure that the blue blood vesels are veins and the red ones are arteries, so @khanacademy , please add notation on the video.

[@faithyunjae]

Wow this guy is awesome! He's explanations are Wayyy clearer and simpler than my biology teacher's:) bravo

[@Xgeneralll]

5:46 "He's got some eyeballs and he's looking at us"....LOL YOU GOTTA LOVE SAL

[@justlaurenclare]

Thank you so much! I didn't understand the circulatory system fully until you explained it into such a great depth!

[@66rthomas]

OMG!!! thank you for these videos. i don't know what i'd do with out you... why didn't i discover you earlier. THANK YOU!

[@sanakhawaja7210]

I followed the link to the previous video however after watching all the videos in the queue, the previous video to this one is not found. I'm trying to search for the video but no luck. Perhaps there is a video that's been taken down or never uploaded? I'd love to watch it. Thank you for teaching us incredible knowledge for our benefit.

[@zaybah7493]

Yay! I understand, your teaching is awesome!

[@NoornabiBaloch]

no words to adore khan academy.. thanks alot for ur this struggle.

[@mareejane16]

just so easy to listen to and it makes sense!

[@dannynygin]

excellent explanation!!!!!!!!!!!!!!!!

[@MasSamurai]

this guy..... is the freaken best

[@issa5021]

man ur very awesome at this im gonna be a botox surgoen,they put injections on the face and make wrinkles shrink.keep everything up and ull enter a competition,awesome vid!

[@Jac0b130]

Thanks alot for your help! you go in so much detail, which is really helpful

[@HalfassDIY]

I always wondered how that worked - thanks !

[@0anar0]

@nexychoco and it does except the pulmonary ones. it's because of the size, if you notice the blood vessel that goes to the lungs it's bigger than the one that comes back from the lungs to the heart. So, bigger --> more pressure --> artery. I think this is the explanation.

[@Splinter5k]

we are going through this in A&P II and this video helped me grasp the information better. thanks khan!

[@boeing747200lr]

Sal, you did an awesome job explaining human heart. Thank you so much.

[@ilikefpsgames1]

thanks man this helped me alot

[@jonmonkey15]

great job, can always use extra study material and you make it easy to understand

[@SmashBrosBrawl]

i wish this guy was my anatomy teacher

[@APTX4869L]

YOU ARE SO AWESOME!!! THANKS A LOT!

[@olaxty1]

Good Job!!!..thanks for this..great videos..

[@jco123psu]

Thank you I am studying for my TEAS exam and this really made things very clear for me. Thank you again!!!

[@simplejacksadventures3215]

THATS A AWESOME VID

[@4soulman]

Dude you laid it down perfect!

[@blah8D]

This video was amazing. It was like the rosetta stone for body systems. It's so clear to understand!

[@sherbet185]

thank you sooooooo much i have a hard time remembering things in lectures and i easily remember with the way you teach, excellent teacher

[@bennybeibe]

wow its sooo helpful u r amazing NNNOOOTTTT

[@Ramija97]

You know what you should do? Come to New Zealand, and personally tutor me. Maybe this way I'll ace my science exams.

[@kemiley56]

thank you so much. your videos are a great help. i have an exam soon and i finally understand.

[@tomasruiz6818]

fascinating

[@susanperkins8113]

Thanks! This was very helpful!!! :)

[@jigleer]

Your vids are great. Cheers bud

[@MalazIbrahim123]

complicated but helpfull

[@rajlesta]

Perfect tutorial... I wish he was my biology tutor... good one

[@SuperRandomGuitar]

This is so useful, I wish you had more videos on my syllabus though!!

[@nehagovindarajan6662]

These videos are funny and are MUCH better than my textbook. All I have to do when I have a test is to watch these videos and voila!

[@ema1171224]

The heart pumps blood that carries oxygen around the body. If the heart becomes damaged, it will have difficulty pumping blood.

[@Cheesemine710]

this is hot stuff... ready for the cumulative test... thanks so much!

[@damlayldz6629]

THANK YOU SO MUCH !

[@kkcc4848]

WOW! that was by the far the best explanation of heart and how it works. Thank you so much :D you're absolutely wonderful :)

[@drbollman]

Your explanation is wrong, but God bless you, and have good health.

[@abckadwa]

Excellent presentation. Thanks!!

[@AnileAjilimE]

Wow, you know how to explain very good. Thank you very much!

[@princessbutterfly786]

ur a great guy....

[@Alexayzia]

such a good video, thank you!

[@TheTricklisted]

i love this video...haha "look, this guy has eye balls"///awesome video...thank you so much who ever made this

[@KS-qu8hi]

Yes, besides in pulmonary circulation, there's another circulation called "Systemic circulation" which covers the rest of the body (kidney, bones, feet, toes, brains) :)

[@MrGreat786]

paused the video halfway just to say this...you mr khan are a legend :)

[@tshirtonthehead]

Thanks!

[@rajat5551]

The left circuit is better gated to high pressure & right circuit is very low in pressure incumbent upon systemic resistance . why ? due to oxygen ?

[@JimmyCurry]

Great vid, great energy, knowledge. Keep it up.

[@zabmaina]

thank you so much for that work..I suggest you to make more anatomy and pshysiology videos for the people that are intrested in that kind of subjects and like your way of teaching :-)

[@shailukala]

@ezbg yea same thing n if u wanna go in detail then go for biology books.

[@rnjsco01]

thank you soo much! :)

[@ElRammo]

The good thing about Sal is that he explains things SO WELL that when he makes a mistake you aren't left wondering what the fuck, you can figure out what he must have meant and don't have all this uncertainty about it.

[@1glicerin1]

this is excelent. NOW I KNOW EVERYTHING!!!!

[@sourichitsazzadeh2629]

Thank you for nice presentation.

[@oOoironhideoOo]

thanks a lot !

[@freddyr6]

Very good video, are you a doctor?

[@shoppittsburghnow]

brilliant video

[@angelheartsolor]

In all directions is in our lives especially when love and equality is a heart center motivation, heart flo in perfect health.

[@selah21740]

So...this is incredibly helpful. Thank you :)

[@Niffie]

@JESUSacoustic Pulmonary Artery carries deoxygenated blood then it goes to the lungs to get oxygens so it'd be oxygenated afterwards it goes back to the heart through Pulmonary Vein, that means Pulmonary Vein carries Oxygenated blood. He said it clearly on this vid. And he didn't get it mixed up.

[@19Nightwing91]

Thank you Sir!! You're awesome.

[@soubasoo4030]

love it, love you !! it's so easy now xD

[@CZ0RZ]

Had no idea what he was talking about until 9:00. The large diagram was way too confusing.

[@shaderricamiller7090]

m

[@lesg1987]

Totally get what you say

[@BurntFlower88]

Thank you so much! I wish I had seen your videos when I took Physiology. :(

[@KS-qu8hi]

No it's not. The pulmonary artery carries away deoxygenated blood from the right ventricle (thus the blue-colored vessel, Arteries=Away) then once it has passed through the capillaries in the lungs, the blood becomes oxygenated (thus the red-colored vessel) and passes through the pulmonary vein (Vein=Return to heart) back to the left atrium. Then it goes on to systemic circulation.

[@omarelmghari8698]

Awesome vid. What video recorder do you use to record your videos?

[@pikae9815]

thanks

[@j.tamburello4053]

This video is a part II -- it starts in the middle of a lecture

[@agentsmith60490]

He uses a Wacom graphics tablet running SmoothDraw 3 and uses a Camtasia Studio screen recording software.

[@tehalchemymaster]

holy shit this video is so good.......