The structure of the eye | Processing the Environment | MCAT

The structure of the eye | Processing the Environment | MCAT | Khan Academy

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11 жыл бұрын

In this video, I review the structure of the eye. By Ronald Sahyouni. Created by Ronald Sahyouni.
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Пікірлер: 114

@ungas8978 9 жыл бұрын

Hey I think you missed the blind spot of the eye, known as the Optic Disc. Excellent and very helpful video though! :)

@Scorpionita13 8 жыл бұрын

The conjunctiva actually does not cover the cornea. It covers the front part of the sclera and the inside of the eyelid. Just wanted people to know!

@daman1193 8 жыл бұрын

+Johanna Malmström THANK YOU i got so confused

@Scorpionita13 8 жыл бұрын

+da man I should know, since I'm studying to become an optician ^^

@daman1193 8 жыл бұрын

good luck

@Scorpionita13 8 жыл бұрын

+da man Thanks, soon finished with my first year :)

@samanthagonah8243 4 жыл бұрын

Yes it honestly got me totally confused had to look it up elsewhere. I am glad someone noted that.

@loving60s 10 жыл бұрын

I believe the area that you referred to as the posterior chamber is actually the vitreous humor; it is important not to confuse the two. The posterior chamber is the small space in front of the suspensory ligaments and behind the iris.

@seangjoka1 8 ай бұрын

@Gurneesucks 10 жыл бұрын

Not only did you explain things well you gave alot of awesome real world examples! You made it interesting and FUN! Good work !

@MFG762 8 жыл бұрын

I'll have to say, I've used Kahn Academy through out my entire college career working my way to earn my degree. I'm shocked that they have put their mark on this annotation for the structure of the eye. The spacial arrangement of the anatomical features is totally misrepresented given that the title of the video is labeled structure of the eye. The time he spent talking about how light is refracted then he draws the optic nerve dead center of the eye... And adding to it the time spent explaining the macula. Kahn should really consider re-doing this video to ensure its thousands of viewers proper education for the optics system.

@rawanghanem1607 3 жыл бұрын

سبحان الله العظيم. شكرا على الشرح البسيط المفهوم thank you.

@gabrielapauli73 10 жыл бұрын

Great video, man! Thanks for clearing things up for me!

@MarttyLovato 8 жыл бұрын

i love your videos, it had helped me a lot

@yusrafathima9294 5 жыл бұрын

The front of the iris covered by thin transparent membrane call the conjuctiva which helps to protect the parts behind it .The conjunctiva Is always kept moist by a fluid made in the tear glands.This fluid contains an Enzyme called Lysozyme which can kill bacteria

@sel6137 3 жыл бұрын

i cannot say enough thank you. Basically this vid saved my life 3 times. got me into my dream school. thank you smsmsm

@StaticDescenTaySC 8 жыл бұрын

Uhm.. the portion between the cornea to the anterior surface of the lens is termed as "Anterior segment" and behind the lens to the anterior surface of the retina is called "Posterior segment"; "Anterior chamber" refers to the space between the cornea and the pupil, posterior to the pupil to the lens is called "posterior chamber." side note, glaucoma can be due to decrease clearance when the iridocorneal junction (in the anterior chamber) reduced in angle/ reduced in drainage.

@chasingsystems 7 жыл бұрын

I dont even do medicine this stuff is just cool. Great channel

@alonnalee5964 10 жыл бұрын

Great information! I had difficulty hearing you though.

@Angel12595 9 жыл бұрын

Greatest video, thank you :)

@meliodad2422 9 жыл бұрын

detail like ma textbook ! nice

@juodasai 9 жыл бұрын

vitreous chamber not posterior:).. its a good video.

@sunitaparmar3619 9 жыл бұрын

It help,s lot of us.Thank you .

@ShanShan-ov3qe 8 жыл бұрын

this is very helpful..

@thirva95 9 жыл бұрын

Awesome very helpful video :)

@TimFleisher 6 жыл бұрын

not sure if you mentioned it but you point out the posterior chamber when it's the posterior segment. posterior chamber is just posterior to the iris. the posterior and anterior segments are what i think you meant. the anterior and posterior chambers are different.

@ismahanw8977 8 жыл бұрын

I'm pretty sure humour means fluid, and not chamber

@islandboy666 7 жыл бұрын

Ismahan W vitrous humor

@torri51 6 жыл бұрын

I think he meant it's in the anterior and Positior chamber

@OneBananaa 9 жыл бұрын

i really liked this video! v informative ^^

@matthewmcguinness2647 9 жыл бұрын

There are actually 3 chambers; the anterior chamber, the posterior chamber and the vitreous chamber.

@traitonm3724 6 жыл бұрын

what a fantastic video. thank you so much, love the illustrations.

@kmcel190 7 ай бұрын

I did not expect to understand this as well as I did, i suppose caffeine had something to do with it 🤣

@AARCHER1212 7 жыл бұрын

brilliant video

@sarah5578 4 жыл бұрын

correction: i think you meant posterior segment or cavity NOT posterior chamber, because the posterior chamber is part of the anterior cavity found anterior to the zonule (suspensory ligament).

@ravenbullard2982 4 жыл бұрын

Awesome video!!!

@benjaminmanzanoperez4502 5 ай бұрын

Amazing lecture, thank you

@LTLTE 6 жыл бұрын

Nice video, but I recommend speaking louder (my volume is all the way up).

@Joe-sr2pm 3 жыл бұрын

that makes me mad lol

@enoushe8996 3 жыл бұрын

i've been watching lots of your video but i'm also curious about what app do you use for drawing? if u dont mind answering thank u

@AudreyVictoria 9 жыл бұрын

WHAT ABOUT THE ZONULES OF ZINN?! -_-

@ungas8978 9 жыл бұрын

They're also known as the Suspensory Ligaments of the Eye, which were mentioned in the video :)

@Ciuwas 6 жыл бұрын

Lol...

@chloepalamos851 9 жыл бұрын

Hi! Would you mind if I used your videos for a Biology project?

@OberoonMarteel 8 жыл бұрын

Thanks

@madihakhan1898 Жыл бұрын

i love this man

@alpha4634 4 жыл бұрын

Thank you 😢

@manaeisurluv 5 жыл бұрын

good job

@ulten516 6 жыл бұрын

Is it just me or does the narrator in this video sound EXACTLY like Kermit the Frog?

@BrightSpirals 6 жыл бұрын

ulten5 He 100% sounds like Kermit the Frog

@tabieeeeee 8 жыл бұрын

Anterior chamber contains both anterior chamber and posterior chamber. The posterior cavity contains vitreous humor.

@vivekpk9357 2 жыл бұрын

Thank you🙏

@monikawiliamu1903 4 жыл бұрын

Hey that's good

@KillerTacos54 5 ай бұрын

Thank you so much

@seniyasurursenu8417 2 ай бұрын

I am ur father

@KolheAmol 10 жыл бұрын

It it just me or the audio is really low?

@orca7278 3 жыл бұрын

it is super low

@everyusernametaken11 Жыл бұрын

One point to note: you mentioned the Cornea "bends the light a little bit" and the Lens "bends it a bit more." This is somewhat misleading as the Cornea does the bulk of the work in bending light, while the Lens only helps with additional fine focusing. The incoming light ray through air is at a refractive index of about 1. The Cornea's refractive index is 1.33 (as it's mostly made of water), and the Lens' refractive index is 1.42 (more like glass). So, the Cornea is responsible for bending the light ~33%, and the Lens another ~6.7%. Secondly, it might be helpful to specify the "red eye" effect is from blood supply in the central retinal artery supplying the retina with blood, rather than the retina itself being tinted red.

@fayexfaye1 9 жыл бұрын

Yikes! Humor does not mean chamber. Humor means fluid. Aqueous humor of the anterior chamber, vitreous humor of the posterior chamber.

@sophier973 3 жыл бұрын

The bulbar conjunctiva stops at the junction between the sclera and cornea; therefore conjunctiva does not cover the cornea.

@VanTM 6 жыл бұрын

In my MCAT book, it says "posterior chamber (production of aqueous humor)", could you please clarify?

@torri51 6 жыл бұрын

Posterior chamber : Starts behind the iris and goes to the lens Filled with Aqueous Humor that helps nourish the cornea and lens . Ciliary Body is what produce Aqueous Humor

@VanTM 6 жыл бұрын

Well because in the video he said "posterior chamber produced vitreous humor" so I'm confused.

@rushhour1 10 жыл бұрын

The conjunctiva lines the inside of the eyelids and covers the sclera (white part of the eye). It does not cover the cornea.

@lilygal24u 10 жыл бұрын

actually it does, I have a textbook in front of me right now that proves you wrong

@Yayyaa100 9 жыл бұрын

lilygal24u it doesn't cover the cornea , sclera and covers the eyelids from inside

@rushhour1 9 жыл бұрын

Sameer Haque Thanks Sameer! Yes that's right, outer edge of the cornea is also known as the corneal limbus.

@samaritandhoowle7682 6 жыл бұрын

hey mahn conjunctiva covers the cornea and its function is to protect it

@kingamv107 6 жыл бұрын

Conjuctiva covers the scleroid's transparent part which is termed as cornea , REMEMBER- Conjuctiva continues with the inner lining of the eyelid.

@freelogen8685 6 жыл бұрын

Oh 2:14 it's Aqueous* humor, but in New Zealand/Britain they spell it as "humour".....or I could be completely wrong I'm not going through my old text-book just to prove a point. *winks*

@jasmithabobbili6474 4 жыл бұрын

Sir 'mong white and blue which is more harm to our eyes?

@ace_gaming4787 Жыл бұрын

❤

@fluffy2688 5 жыл бұрын

I’m pretty sure its not suspensory ligament, its Ciliary ligament

@delainestrandberg1541 9 жыл бұрын

Some structures seems "new," s the black choroid, as compared to structure of the eye in the 70's, or better explained than a medical doctor, who did not use colored chalk.

@Whiteshade93 5 жыл бұрын

hello,what is the name of the field of science that studies the eye function?

@barathnr6000 5 жыл бұрын

Opthalmology

@BrotherofSki 8 жыл бұрын

its just so slow.

@saranam1576 6 жыл бұрын

his voice makes me very sleepy. It's like a student who just read the material is talking. Next

@rewarishi 9 жыл бұрын

Very well explained

@berhanutsige7343 3 жыл бұрын

👁👁

@momo82012 2 ай бұрын

I am bit confused about choroid. So black part of pupil is choroid? ( 8:54 )

@seniyasurursenu8417 2 ай бұрын

No it is the part of the eye that nourish the eye with blood vessels. *Creator

@eddies8674 3 жыл бұрын

Demonic start to the video?

@Yayyaa100 9 жыл бұрын

Great video even there's few mistakes .

@sandrapassani1 7 жыл бұрын

If our pupill is black because of the black choroidea, and cats have a shiny choroidea, why aren't their pupills shiny?

@truly2special 7 жыл бұрын

they are.

@octaviashabazz7027 Жыл бұрын

good video, but you were talking too low

@abdallahbelhadj6462 3 жыл бұрын

Man this guy isn't too excited about making this video lmao

@unitedspacepirates9075 4 жыл бұрын

Zombie Jesus Saves... the eyes for last.

@Rodztar13 10 жыл бұрын

Cant hear you

@abhi_exe4774 5 жыл бұрын

What is the order of ganglion cells, bipolar neurons & photoreceptor cells?

@BrightSpirals 6 жыл бұрын

The guy sounds like Kermit the frog or is it just me who hearing it ?

@ryut6638 3 жыл бұрын

As I know... conjunctiva doesn’t cover the cornea. I stop watching this video after he said the conjunctiva covers the cornea.

@YousefMohamed-fn6oi 7 жыл бұрын

wtf? humour

@TheZombo66 5 жыл бұрын

So monotone

@fatimahtahir4727 4 жыл бұрын

Your voice is too low. Its hard to listen

@gabethebabe6598 3 жыл бұрын

This guy is totally confused about lots of things - not just the chamber nomenclature, but the ciliary body function (he doesn't understand the function of different features) as well as a bunch of other things :(

@tbean5990 Жыл бұрын

YO my boy please speak up. I had to put on gaming headphones at maximum volume and still could not hear you. I also was munching on some cheerios

@CalebDiT 6 жыл бұрын

I'm not a child such that I need to see smiley faces in order to "like" your videos. If you really think your audience members are children, this material seems inappropriate.

@monday2471 6 жыл бұрын

i didn't like this video. so unclear and the narrator contradicts himself so many times

@lawyerdoctor 7 жыл бұрын

I don't think drawing the eye is particularly helpful. A diagram of the eye and a pointer indicating the parts that are being discussed would be easier to follow. Missed the mark for sure on this video.